Devices and methods for excluding the left atrial appendage

ABSTRACT

Devices and methods are described for occluding the left atrial appendage (LAA). The device excludes the LAA from blood flow to prevent blood from clotting within the LAA and subsequently embolizing, particularly in patients with atrial fibrillation. The implantable device is delivered via transcatheter delivery into the LAA and secured within the LAA. The implant comprises an expandable and compliant frame and an expandable and conformable tubular foam body carried by the frame. The device may have a thromboresistant cover at a proximal end and a thromboresistant coating on the foam body. The frame may have recapture struts inclining radially outwardly in the distal direction from a central hub. The frame may have axially extending side wall struts, with adjacent pairs of side wall struts joined at one or more apexes. Anchors extend from the frame to engage tissue. The anchors can also be reversible to allow retraction of the anchors and repositioning or retrieval of the device.

INCORPORATION BY REFERENCE TO ANY RELATED APPLICATIONS

Any and all applications for which a foreign or domestic priority claimis identified in the Application Data Sheet as filed with the presentapplication are hereby incorporated by reference under 37 CFR 1.57.

This application claims the benefit of priority to U.S. provisionalpatent application No. 62/459,503, entitled DEVICES AND METHODS FOREXCLUDING THE LEFT ATRIAL APPENDAGE and filed Feb. 15, 2017, and to U.S.provisional patent application No. 62/413,632, entitled MULTIFUNCTIONALLEFT ATRIAL APPENDAGE (LAA) OCCLUDER and filed Oct. 27, 2016, thedisclosure of each of which is hereby incorporated by reference hereinin its entirety for all purposes and forms a part of this specification.

BACKGROUND Field

This development relates generally to systems, devices and methods forexcluding the left atrial appendage (LAA). In particular, systems,devices and methods for excluding the LAA using an expandable foamimplant with a deployable and compliant frame are described herein.

Description of the Related Art

Atrial fibrillation (Afib) is a condition in which the normal beating ofthe left atrium (LA) is chaotic and ineffective. The left atrialappendage (LAA) is a blind pouch off the LA. In patients with Afib bloodstagnates in the LAA facilitating clot formation. These clots (or clotfragments) have a tendency to embolize or leave the LAA and enter thesystemic circulation. A stroke occurs when a clot/clot fragmentembolizes and occludes one of the arteries perfusing the brain.Anticoagulants, e.g. Coumadin, have been shown to significantly reducethe stroke risk in Afib patients. These drugs reduce clot formation butalso increase bleeding complications including hemorrhagic strokes,subdural hematoma, and bleeding in the gastrointestinal tract.

There are about eight million people in the US and EU with Afib. About4.6 million of these patients are at a high risk for stroke and wouldbenefit from anticoagulation. A large portion of these patients cannottake anticoagulants due to an increased bleeding risk, leaving theirstroke risk unaddressed. The prevalence of Afib increases with age.

Existing devices for occluding the LAA have drawbacks. Existing devicesare offered in many sizes and must be closely matched to the highlyvariable LAA anatomy. This is difficult to do using fluoroscopy andoften requires adjunctive imaging in the form of transesophagealechocardiography (TEE), cardiac CT and MRI, all with three dimensionalreconstructions. If the device is significantly oversized, the LAAostium may become overstretched leading to tearing, resulting inbleeding into the pericardial space. If the device is too small, it willnot adequately seal the ostium and may be prone to embolization. Even ifsized correctly, the device forces the oval LAA ostium to take the roundshape of the device, often resulting in residual leakage at the edgesdue to poor sealing.

Existing devices require sufficient spring force or stiffness to sealand anchor to surrounding tissue. If too stiff, these devices may leadto leaking of blood through the tissue into the pericardial space whichmay lead to cardiac tamponade. Furthermore, the geometry of thesedevices limits repositioning once the implant is fully expanded.Existing devices also complicate delivery by requiring positioning inthe LAA coaxial to the axis of the LAA.

There is therefore a need for an improved LAA occlusion device.

SUMMARY

The embodiments disclosed herein each have several aspects no single oneof which is solely responsible for the disclosure's desirableattributes. Without limiting the scope of this disclosure, its moreprominent features will now be briefly discussed. After considering thisdiscussion, and particularly after reading the section entitled“Detailed Description,” one will understand how the features of theembodiments described herein provide advantages over existing systems,devices and methods for left atrial appendage (LAA) occlusion.

The following disclosure describes non-limiting examples of someembodiments. For instance, other embodiments of the disclosed systemsand methods may or may not include the features described herein.Moreover, disclosed advantages and benefits can apply only to certainembodiments and should not be used to limit the disclosure.

Devices and methods are described for occluding the LAA (LAA) to excludethe LAA from blood flow to prevent blood from clotting within the LAAand subsequently embolizing, particularly in patients with atrialfibrillation. An LAA occlusion device is delivered via transcatheterdelivery into the LAA and anchored using a compliant frame and foambody. The device conforms to the oval shape of the LAA with superiorsealing effect, does not require an excessive number of sizes and thusnegates the need for extensive pre-procedure imaging, and can bedelivered off-axis thereby allowing for simpler delivery procedure,among other advantages.

A foam body, which can be tubular in shape, and a compliant frame insideor within the foam body, are described that are collapsed for deliveryand then expand in place within the LAA. The foam body may have acoating at least partially on the outer surface(s) of the foam body. Thecoating may be a layer of Polytetrafluoroethylene (PTFE). The device isanchored by structural anchors of the frame and/or by tissue ingrowthfrom the left atrium (LA) and LAA into the foam. Some embodiments areadditionally or alternatively anchored by independent or integratedrepositionable anchors, by barbs, and/or by distal anchoring elements.For example, anchors extending from a compliant frame are describedwhich deploy through the compressible foam plug. In some embodiments,repositionable atraumatic anchor system embodiments are also disclosedwhich can be independent structures or integral to the foam plug and/orskin.

The foam body may be at least partially covered by a proximal end cover.The cover may be an expanded Polytetrafluoroethylene (ePTFE) cover. Thecover provides several advantages, such as the following: sufficientlystrong to enable handling of the plugs without tearing; allow forrepositioning and retrieval of the plugs; provides a thromboresistantsurface within the LA which will encourage formation of a neointima;assist in the creation of occlusion zones designed to encouragethromboresistance and endothelialization from the blood and adjacenttissue and anchoring zones designed to promote fast and tenacious tissueingrowth into the compressible implant from the adjacent non-bloodtissue; and can assist in closure at the ostium. The cover, e.g. alayer, jacket or skin, etc., can be independent or can be attached tothe foam body, for example with sutures, adhesives, etc. In someembodiments, retrieval finials can be attached at one or more points toaid in retrieval of an embolized device and to increase radiopacity.

Some embodiments are tracked over a guidewire and have a guidewire lumenwithin the foam that is expandable, to allow for placement of theguidewire, and then is self-closing upon removal of the guidewire. Someembodiments do not require a guidewire lumen. Further, some embodimentsmay be multi-functional and include features for ablation,pressure-sensing, drug-elution, pacing, electrical isolation, etc.

In one aspect, a left atrial appendage occlusion device is described.The device comprises a conformable, tubular foam body, a compressibleside wall and an expandable support. The conformable, tubular foam bodyhas a closed proximal end and a distal end. The compressible side wallextends between the proximal end and the distal end, and defines acentral cavity. The expandable support is within the body and configuredto compress the side wall against a wall of a left atrial appendage.

In some embodiments, the side wall may have an uncompressed thickness ofat least about 0.5 mm. The compressible side wall may have anuncompressed thickness of at least about 1.5 mm. The compressible sidewall may have an uncompressed thickness of about 2.5 mm. Thecompressible side wall may extend in a distal direction beyond a distalend of the support by at least about 2 mm in an unconstrained, expandedstate. The compressible side wall may extend in a distal directionbeyond a distal end of the support by about 5 mm in an unconstrained,expanded state. The compressible side wall may comprise a foam having aplurality of interconnected reticulations and voids, and furthercomprising a PTFE coating on at least some of the interconnectedreticulations. The closed proximal end may comprise a foam end wall. Thefoam end wall may further comprise a cover. The cover may compriseePTFE. The expandable support may be self-expandable. The expandablesupport may be in the central cavity. The tubular foam body may besubstantially cylindrical in an unconstrained, expanded state.

In another aspect, a self-expandable, atraumatic occlusion device isdescribed. The device is configured to conform to the side wall of aleft atrial appendage. The device comprises a compressible open cellfoam body, a self-expandable support and a proximal end wall. Thecompressible open cell foam body has a tubular foam side wall and acentral cavity. The expandable support is within the cavity. Theproximal end wall is on the foam body. The proximal end wall ispositioned proximally of the proximal end of the support, and the foamside wall extends distally beyond the distal end of the support to forma distal, atraumatic bumper for preventing contact between the supportand a wall of the left atrial appendage in an implantation in which acentral longitudinal axis of the occlusion device is non-parallel to aprimary longitudinal axis of the left atrial appendage.

In another aspect, a left atrial appendage occlusion device isdescribed. The device comprises an expandable tubular foam cup and anexpandable frame. The expandable tubular foam cup has a proximal end, adistal end, a tubular side wall and a proximal end wall. The side wallhas a thickness of at least about 1.0 mm and a porosity of at leastabout 85% open void content. The expandable frame is configured to pressthe side wall into conforming contact with a wall of the left atrialappendage.

In some embodiments, the tubular side wall may have a thickness of atleast about 2 mm. The tubular side wall may have a void content of atleast about 90%. The tubular side wall may have an average pore size ofat least about 100 microns. The tubular side wall may have an averagepore size of at least about 200 microns. The tubular side wall may beprovided with a thromboresistant coating. The thromboresistant coatingmay comprise PTFE. The proximal end wall may be provided with athromboresistant cover. The frame may further comprise at least threerecapture struts inclining radially inwardly in the proximal directionto a hub. The frame may comprise a plurality of axially extending sidewall struts, with adjacent pairs of side wall struts joined at an apex.The frame may comprise at least six proximally facing apexes and atleast six distally facing apexes. Each recapture strut may be joined toa unique proximally facing apex on the frame. The recapture struts maybe integrally formed with the frame. The device may further comprise alumen through the hub. The device may further comprise anchors to securethe device to tissue. The anchors may be flexible anchors configured toextend through the foam side wall at an inclined angle.

In another aspect, a conformable LAA occlusion device is described. Thedevice comprises a compressible tubular foam wall. The wall comprises areticulated, cross linked matrix having at least about 90% void content,an average cell size within the range of from about 250-500 microns, awall thickness of at least about 2 mm and a compressive strength of atleast about 1 psi. In some embodiments, the compressive strength iswithin a range of from about 1 psi to about 2 psi. In some embodiments,the device may have an expandable support configured to compress theside wall against a wall of a left atrial appendage.

In another aspect, a LAA occlusion device is described. The deviceincludes an open cell foam body and an internal locking system. The bodyhas a proximal end, a distal end and an outer skin. The proximal end isconfigured to face a left atrium and the distal end is configured toface the LAA following implantation in the LAA. The body can becompressed for delivery within a delivery catheter and can self-expandwhen removed from the delivery catheter. The internal locking system iscoupled with the body and comprises at least one deployable tissueanchor. The deployable anchor is configured to deploy from a constrainedconfiguration within the body to a deployed configuration where a tissueengaging segment of the anchor extends outside the body to secure thebody within the LAA. The deployable anchor is configured to deploy tothe deployed configuration after the body expands within the LAA. Thedeployable anchor may be retractable from the deployed configuration toa retracted configuration within the body.

In some embodiments, the internal locking system further comprises aplurality of the deployable anchors rotatably coupled with the body,wherein the plurality of anchors are configured to rotate to thedeployed and retracted configurations. The internal locking system maycomprise four of the deployable anchors. In some embodiments, the bodyfurther comprises a plurality of axially extending slots correspondingto the plurality of anchors, wherein each of the plurality of anchors isconfigured to deploy and retract through the corresponding axial slot.

In some embodiments, the internal locking system further comprises arestraint that restrains the anchor in the constrained configuration,and the anchor is deployed from the constrained configuration to thedeployed configuration by removing the restraint from the anchor. Therestraint may be a sheath that restrains the anchor in the constrainedconfiguration by covering the anchor, wherein the anchor is deployedfrom the constrained configuration to the deployed configuration byremoving the sheath from covering the anchor. The restraint may be alasso that restrains the anchor in the constrained configuration bysurrounding the anchor, and the anchor is deployed from the constrainedconfiguration to the deployed configuration by removing the lasso fromsurrounding the anchor.

In some embodiments, the internal locking system further comprises amoveable mount coupled with an end of the anchor, and the anchor isdeployed from the constrained configuration to the deployedconfiguration by axially moving the mount.

In some embodiments, the internal locking system further comprises aconstraint configured to move over the anchor to cause the anchor toretract. The constraint may be a ring configured to slide over theanchor to cause the anchor to retract.

In some embodiments, the skin comprises ePTFE.

In some embodiments, the device further comprises at least one tissueingrowth surface on a sidewall of the body.

In some embodiments, the device further comprises a plurality ofopenings in the skin to permit tissue ingrowth into the open cell foambody. The plurality of openings of the skin may be located in ananchoring region of the device located at least between the proximal anddistal ends of the device, and the device may further comprise anocclusion region located at the proximal end of the device andconfigured to encourage thromboresistance and endothelialization fromthe blood and adjacent tissue.

In another aspect, a LAA closure system is described. The systemcomprises a delivery catheter and a LAA occlusion device. The deliverycatheter comprises an elongate flexible tubular body, having a proximalend and a distal end and at least one lumen extending therethrough. TheLAA occlusion device is configured to be compressed within the deliverycatheter and to self-expand upon deployment from the delivery catheter.The device comprises a self-expandable open cell foam body coupled withan internal locking system. The internal locking system comprises adeployable anchor configured to deploy from a constrained configurationto a deployed configuration after the body expands within the LAA and isconfigured to retract from the deployed configuration to a retractedposition within the body.

In some embodiments, the system further comprises an axially movabledeployment control extending through a lumen of the body, for deployingthe deployable anchor. The system may further comprise an axiallymovable deployment control extending through a lumen of the body, fordeploying the foam body from the distal end of the closure system. Theinternal locking system may further comprise a restraint that restrainsthe anchor in the constrained configuration, and the anchor is activelydeployed from the constrained configuration to the deployedconfiguration by removing the restraint from the anchor using an axiallymovable deployment control extending through a lumen of the body. Theinternal locking system may further comprise a moveable mount coupledwith an end of the anchor, and the anchor is actively deployed from theconstrained configuration to the deployed configuration by axiallymoving the mount using an axially movable deployment control extendingthrough a lumen of the body.

In another aspect, a method of excluding a LAA is described. The methodcomprises advancing a guidewire into the LAA, advancing a distal end ofa delivery catheter over the guidewire and into the LAA, and deploying aLAA occlusion device from the distal end of the delivery catheter. Thedevice comprises an expandable foam body coupled with an internallocking system having a deployable anchor, and the body expands withinthe LAA upon deploying from the distal end of the delivery catheter. Themethod further comprises actively deploying the deployable anchor afterthe body expands within the LAA. The deployable anchor is configured toretract from the deployed configuration to a retracted position withinthe body. In some embodiments, the method further comprises retractingthe deployable anchor from the deployed configuration to the retractedposition.

In another aspect, a LAA occlusion device is described. The devicecomprises an expandable foam body and an internal locking system. Thebody can be compressed for delivery within a delivery catheter and canself-expand when removed from the delivery catheter. The internallocking system is coupled with the body and comprises a deployableanchor configured to deploy from a constrained configuration within thebody to a deployed configuration where the anchor extends outside thebody to secure the body within the LAA. The body is configured to expandupon removal from the delivery catheter, and the deployable anchor isconfigured to deploy to the deployed configuration after the bodyexpands.

In another aspect, a LAA occlusion device is described. The devicecomprises an expandable foam body and an internal locking system. Thebody can be compressed for delivery within a delivery catheter and canself-expand when removed from the delivery catheter. The internallocking system is coupled with the body and comprises a deployableanchor configured to deploy from a constrained configuration within thebody to a deployed configuration where the anchor extends outside thebody to secure the body within the LAA. The deployable anchor isconfigured to retract from the deployed configuration to a retractedconfiguration within the body such that the body can be repositionedwithin the LAA.

In another aspect, a LAA occlusion device is described. The devicecomprises an expandable tubular frame, an expandable tubular foam layerand a tissue scaffold. The expandable tubular frame has a proximal end,a distal end and a central lumen. The expandable tubular foam layer iscarried by the frame and has a thickness of at least about 0.5 mm. Theemboli retention layer is carried by the frame and encloses the lumen atthe proximal end.

In some embodiments, the foam layer may have a thickness of at leastabout 1 mm. The foam layer may have a thickness of at least about 2.5mm. The foam layer may have a void content of at least about 80%. Thefoam layer may have a void content of at least about 90%. The foam layermay have an average pore size of at least about 100 microns. The foamlayer may have an average pore size of at least about 200 microns. Thefoam layer may extend across the proximal end of the frame to form thetissue scaffold. The tissue scaffold may be provided with athromboresistant coating. The tissue scaffold may be provided with athromboresistant layer. The thromboresistant coating or layer maycomprise PTFE. The thromboresistant coating or layer may comprise ePTFE.The frame may further comprise at least three recapture struts incliningradially inwardly in the proximal direction to a hub.

In some embodiments, the foam layer extends across the proximal end ofthe frame to form the tissue scaffold, and the frame may comprise aplurality of axially extending side wall struts, with adjacent pairs ofside wall struts joined at an apex. The device may comprise at least sixproximally facing apexes and at least six distally facing apexes. Thedevice may comprise at least three recapture struts joined at a proximalhub, where each recapture strut has a distal end joined to the frame.Each recapture strut may be joined to a unique proximally facing apex onthe frame. The recapture struts may be integrally formed with the frame.The device may further comprise a lumen through the hub.

In some embodiments, the device may comprise anchors to secure thedevice to tissue. The anchors may be static anchors that are configuredto deploy upon deployment of the device from a delivery catheter. Theanchors may be constrained anchors that are configured to becontrollably released into a deployed configuration after expansion ofthe foam. The anchors may be dynamic anchors that are configured to bedeployed from a contracted configuration to a deployed configuration andare further configured to be retracted from the deployed configurationback to a retracted configuration. The anchors may be further configuredto be retracted from the deployed configuration back to the contractedconfiguration.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other features of the present disclosure will becomemore fully apparent from the following description and appended claims,taken in conjunction with the accompanying drawings. Understanding thatthese drawings depict only several embodiments in accordance with thedisclosure and are not to be considered limiting of its scope, thedisclosure will be described with additional specificity and detailthrough use of the accompanying drawings. In the following detaileddescription, reference is made to the accompanying drawings, which forma part hereof. In the drawings, similar symbols typically identifysimilar components, unless context dictates otherwise. The illustrativeembodiments described in the detailed description, drawings, and claimsare not meant to be limiting. Other embodiments may be utilized, andother changes may be made, without departing from the spirit or scope ofthe subject matter presented here. It will be readily understood thatthe aspects of the present disclosure, as generally described herein,and illustrated in the drawing, can be arranged, substituted, combined,and designed in a wide variety of different configurations, all of whichare explicitly contemplated and make part of this disclosure.

FIG. 1 shows the anatomy of the left atrium (LA) and left atrialappendage (LAA).

FIG. 2 shows an LAA with an embodiment of an LAA occlusion deviceimplanted in the LAA and that uses adhesive.

FIG. 3 shows an x-ray image of an embodiment of an LAA occlusion device.

FIG. 4 shows an LAA with an embodiment of an LAA occlusion device anddistal anchor implanted in the LA.

FIG. 5 shows an embodiment of a screw anchor that may be used with thevarious LAA occlusion devices described herein.

FIG. 6 shows a longitudinal cross section of an embodiment of an LAAocclusion device.

FIGS. 7-15 are sequential schematic cross section views of an embodimentof an LAA and delivery system showing delivery and anchoring techniquesthat may be used with the various LAA occlusion devices describedherein, including but not limited to the devices of FIGS. 85A-90D.

FIG. 16 is a side cross section view of an embodiment of an LAAocclusion device having a foam body, frame and proximal cover.

FIG. 17 is a side cross section view of an embodiment of an LAAocclusion device having metal coils and foam.

FIG. 18 is a side view of an embodiment of an LAA occlusion devicehaving a single metal coil.

FIG. 19 is a side view of an embodiment of an LAA occlusion devicehaving a dilating distal tip.

FIG. 20 is a side cross section view of an embodiment of an LAAocclusion device having proximal and distal caps.

FIG. 21 is a schematic of an embodiment of an implant delivery systemthat may be used with the various LAA occlusion devices describedherein, including but not limited to the devices of FIGS. 85A-90D.

FIG. 22 is a schematic of an embodiment of a delivery of an expandingfoam system that may be used with the various LAA occlusion devicesdescribed herein, including but not limited to the devices of FIGS.85A-90D.

FIG. 23 is a side view of a plug with barbs that may be used with thevarious LAA occlusion devices described herein, including but notlimited to the devices of FIGS. 85A-90D.

FIG. 24 shows an embodiment of an LAA occlusion device having aretrieval suture attachment that may be used with the various LAAocclusion devices described herein, including but not limited to thedevices of FIGS. 85A-90D.

FIGS. 25A-26 show embodiments of distal anchoring systems that may beused with the various LAA occlusion devices described herein, includingbut not limited to the devices of FIGS. 85A-90D.

FIGS. 27A-27G are various views of an embodiment of an LAA occlusiondevice with an internal locking system that may be used with the variousLAA occlusion devices described herein, including but not limited to thedevices of FIGS. 85A-90D.

FIGS. 28A-28D are various views of an embodiment of an internal lockingsystem that may be used the device of FIGS. 27A-27G.

FIGS. 29A-29B are sequential side views of an unlocking mechanism thatmay be used with the device of FIGS. 27A-27G.

FIG. 30 is a side view of an embodiment of an LAA occlusion devicehaving flexible anchors that may be used with the various LAA occlusiondevices described herein, including but not limited to the devices ofFIGS. 85A-90D.

FIGS. 31-32 are side views of an embodiment of an LAA occlusion devicehaving flexible anchors and stiffening tubular members configurationthat may be used with the various LAA occlusion devices describedherein, including but not limited to the devices of FIGS. 85A-90D.

FIG. 33 is a side view of an embodiment of an LAA occlusion devicehaving discrete attachments of an outer skin to an internal foam thatmay be used with the various LAA occlusion devices described herein,including but not limited to the devices of FIGS. 85A-90D.

FIG. 34 is a side view of the device of FIG. 34 including an outer rim.

FIG. 35 is a side view of an embodiment an LAA occlusion device havinganchors with deployed V-tips that may be used with the various LAAocclusion devices described herein, including but not limited to thedevices of FIGS. 85A-90D.

FIG. 36 is a side view of an embodiment an LAA occlusion device havingdeployed anchors with V-tips that may be used with the various LAAocclusion devices described herein, including but not limited to thedevices of FIGS. 85A-90D.

FIGS. 37A-37C are side views of various embodiments of anchors that maybe used with the various LAA occlusion devices described herein,including but not limited to the devices of FIGS. 85A-90D.

FIG. 38 is a side view of an embodiment of an LAA occlusion deviceimplanted inside an LAA.

FIGS. 39A-39B are perspective views of an embodiment of a deployableanchor that may be used with the various LAA occlusion devices describedherein, including but not limited to the devices of FIGS. 85A-90D.

FIGS. 40A-40B are perspective views of an embodiment of a deployableanchor that may be used with the various LAA occlusion devices describedherein, including but not limited to the devices of FIGS. 85A-90D.

FIGS. 41A-41B are perspective views of an embodiment of a deployableanchor that may be used with the various LAA occlusion devices describedherein, including but not limited to the devices of FIGS. 85A-90D.

FIGS. 42A-42D are various views of embodiments external deployableanchors that may be used with the various LAA occlusion devicesdescribed herein, including but not limited to the devices of FIGS.85A-90D.

FIGS. 43A-43C are sequential side views of an embodiment of a deploymentconstraint that may be used with the various LAA occlusion devicesdescribed herein, including but not limited to the devices of FIGS.85A-90D.

FIGS. 44A-44C are side views of an embodiment of an adjustable two stageanchor system that may be used with the various LAA occlusion devicesdescribed herein, including but not limited to the devices of FIGS.85A-90D.

FIG. 45A is a cross-sectional view of an embodiment of an LAA occlusiondevice shown in an expanded configuration and having a foam cup body,proximal cover, and a deployable frame that includes a hub, recapturestruts and a tubular body.

FIGS. 45B and 45C are, respectively, a distal end view and a proximalperspective view of the device of FIG. 45A.

FIG. 46 is a distal end view of the LAA occlusion device of FIG. 45A.

FIGS. 47A-47B are perspective and side views respectively of the LAAocclusion device of FIG. 45A having a single piece internal frame.

FIG. 48 is a perspective view of the device of FIG. 45A.

FIGS. 49-50 are side views of the device of FIG. 45A as attached to adelivery catheter shown, respectively, in embodiments of an expandedconfiguration and a partially collapsed configuration.

FIGS. 51-55 are schematics showing various embodiments of static barbsthat may be used with the various occlusion devices described herein,such as the devices of FIG. 45A or 85A.

FIGS. 56-58 are schematics showing various embodiments of constrainedbarbs that may be used with the various occlusion devices describedherein, such as the devices of FIG. 45A or 85A.

FIGS. 59-65 are schematics showing various embodiments of dynamic barbsthat may be used with the various occlusion devices described herein,such as the devices of FIG. 45A or 85A.

FIGS. 66A-66C are side views of the implant of FIG. 45A having aproximal cover.

FIG. 67 shows side and end views of an embodiment of an implant havinggrappling hook anchors.

FIGS. 68A-68B are side and end views respectively of an embodiment of animplant having a thicker distal bumper.

FIG. 69 is a side view of an embodiment of an implant having aconstrained anchor deployed in a secondary step.

FIGS. 70-72 depict embodiments of an implant having distal anchors andproximal speed bumps.

FIGS. 73-75 depict embodiments of an implant having distal loops.

FIGS. 76-77 depict embodiments of an implant having perfusion elements.

FIG. 78 is a side view of an embodiment of an LAA occlusion devicehaving ablative features that may be incorporated with the various LAAocclusion devices described herein.

FIG. 79 is a side view of an embodiment of an LAA occlusion devicehaving pressure-sensing features that may be incorporated with thevarious LAA occlusion devices described herein.

FIG. 80 is a side view of an embodiment of an LAA occlusion devicehaving drug elution features that may be incorporated with the variousLAA occlusion devices described herein.

FIG. 81 is a side view of an embodiment of an LAA occlusion devicehaving pacing/defibrillatory features that may be incorporated with thevarious LAA occlusion devices described herein.

FIGS. 82-84 depict various systems and methods for electricallyisolating the LAA that may be used with the various LAA occlusiondevices described herein.

FIGS. 85A-85C are proximal, distal and side views, respectively, of anembodiment of an LAA occlusion device having a compressible foam body,an expandable frame, and a proximal cover.

FIGS. 86A-86B are side and cross-section views, respectively, of thecompressible foam body of FIGS. 85A-85C.

FIG. 86C is a cross-section view of the foam body of FIGS. 85A-85C withthe expandable frame.

FIGS. 87A-87C are top perspective, side, and cross-section views ofanother embodiment of an LAA occlusion device.

FIG. 88 is a top view of an embodiment of a proximal cover shown in aflat configuration that may be used with the various LAA occlusiondevices described herein.

FIGS. 89A and 89B are side perspective and proximal perspective views,respectively, of the frame of FIGS. 85B and 86C shown in a deployedconfiguration.

FIGS. 90A-90C are sequential proximal perspective views of an embodimentof a frame showing assembly of a cap and pin with the frame that may beused with the various LAA occlusion devices described herein.

FIG. 90D is a distal perspective view of the cap of FIGS. 90A-90C.

FIG. 91 is a side view of an embodiment of a loading system for loadingthe device of FIGS. 85A-85C into a delivery catheter.

FIG. 92 is a side view of a schematic of a transcatheter delivery systemfor delivering the device of FIGS. 85A-85C via an artery or vein.

FIGS. 93A and 93B are proximal and distal perspective views respectivelyof a tether release system that may be used with the device of FIGS.85A-85C.

While the above-identified drawings set forth presently disclosedembodiments, other embodiments are also contemplated, as noted in thediscussion. This disclosure presents illustrative embodiments by way ofrepresentation and not limitation. Numerous other modifications andembodiments can be devised by those skilled in the art which fall withinthe scope and spirit of the principles of the presently disclosedembodiments.

DETAILED DESCRIPTION

The following detailed description is directed to certain specificembodiments of the development. In this description, reference is madeto the drawings wherein like parts or steps may be designated with likenumerals throughout for clarity. Reference in this specification to “oneembodiment,” “an embodiment,” or “in some embodiments” means that aparticular feature, structure, or characteristic described in connectionwith the embodiment is included in at least one embodiment of theinvention. The appearances of the phrases “one embodiment,” “anembodiment,” or “in some embodiments” in various places in thespecification are not necessarily all referring to the same embodiment,nor are separate or alternative embodiments necessarily mutuallyexclusive of other embodiments. Moreover, various features are describedwhich may be exhibited by some embodiments and not by others. Similarly,various requirements are described which may be requirements for someembodiments but may not be requirements for other embodiments. Referencewill now be made in detail to embodiments of the invention, examples ofwhich are illustrated in the accompanying drawings. Wherever possible,the same reference numbers will be used throughout the drawings to referto the same or like parts.

The devices and related methods are described herein in connection withuse in occluding, i.e. excluding, a LAA (LAA). The various figures showvarious embodiments of LAA occlusion devices, systems and methods fordelivery of the LAA occlusion devices, and/or methods of using thedevice to occlude a LAA. The various systems, devices and methodsdescribed herein may include the same or similar features and/orfunctionalities as other LAA occlusion systems, devices and methods asdescribed, for example, in U.S. application Ser. No. 14/203,187 entitled“DEVICES AND METHODS FOR EXCLUDING THE LAA” and filed on Mar. 10, 2014,and/or as described in U.S. Provisional Application No. 62/240,124entitled “DEVICES AND METHODS FOR EXCLUDING THE LAA” and filed on Oct.12, 2015, the entire disclosure of each of which is incorporated hereinby reference for all purposes and forms a part of this specification.

Some embodiments of an LAA occlusion device 3000 include a foam body3002, a deployable and compliant frame 3040, and a proximal cover 3100,as primarily shown and described for example with respect to FIGS.85A-90D. Other features and functionalities that the device 3000 mayinclude and employ are shown and described with respect to FIGS. 1-84and 91-93B.

The heart 100 is shown in FIG. 1 with the left atrial appendage (LAA)102, which is a cavity emanating from the left atrium (LA) 104. The LAA102 is quite variable in shape in all dimensions. If the heart is notbeating normally, a condition called atrial fibrillation, blood withinthe LAA becomes stagnant which promotes clot formation. If blood clotswithin the LAA, the clots may pass from the LAA 102 to the LA 104, tothe left ventricle 106 and out of the heart 100 into the aorta. Vesselsthat bring blood to the brain branch off the aorta. If the clot passesto the brain via these vessels, it may get stuck and occlude a smallvessel in the brain which then causes an ischemic stroke. Strokes havesevere morbidities associated with them. The opening of the LAA 102 tothe LA 104 is called an ostium 110. The ostium 110 is oval, highlyvariable and dependent on loading conditions, i.e., left atrialpressure. An object of the LAA occlusion devices described herein is toocclude the ostium 110 thereby sealing off the LA 104 from the LAA 102.

One embodiment of an LAA occlusion device is shown in FIG. 2. Theocclusion device or plug 204 is placed within the LAA 200 at its openingto the LA 202. It is understood that the “plugs” described herein, suchas the plug 204, may have the same or similar features as otherimplantable “devices” or “implants” described herein, such as the device10, device 1020, device 3000, foam body 3002, etc., and vice versa. Theplug 204 comprises an expandable media such as an open cell foam whichenables collapse and expansion of the plug 204 and also to enhanceingrowth of tissue into the foam. The foam plug 204 is at leastpartially encapsulated within a thin strong layer 206 such as ePTFE(expanded polytetrafluoroethylene), polyolefin or polyester. The layer206 may be referred to herein as a “skin” or “cover” and the like.Alternatively, bioabsorbable materials could be utilized such as PLA,PGA, PCL, PHA, or collagen. This thin encapsulating layer 206 can beoriented or otherwise modified to be elastomeric in at least onedirection, such as radially. The layer 206 may have the same or similarfeatures and/or functionalities as the cover 3100, and vice versa.

The plug 204 may be made of polyurethane, polyolefin, PVA, collagenfoams or blends thereof. One suitable material is apolycarbonate-polyurethane urea foam with a pore size of 100 μm-250 μmor 250 μm-500 μm and 90-95% void content. The foam could benon-degradable or use a degradable material such as PLA, PGA, PCL, PHA,and/or collagen. If degradable, the tissue from the LAA will grow intothe foam plug and replace the foam over time. The plug 204 may becylindrical in shape in an unconstrained expansion, but it may also beconical for example with its distal end smaller than the proximal end orreversed. It could also be oval in cross section to better match theopening of the LAA.

The foam plug 204 is oversized radially in an unconstrained expansion tofit snuggly into the LAA and may be 5-50 mm in diameter depending on thediameter of the target LAA. In a free, unconstrained state, the axiallength “L” of the plug is less than its outer diameter “D” such that theL/D ratio is less than 1.0. In some embodiments, this ratio may begreater than 1.0. The compliance of the foam material is designed suchthat it pushes on the walls of the LAA with sufficient force to maintainthe plug 204 in place but without overly stretching the LAA wall. Thefoam and/or skin also conforms to the irregular surfaces of the LAA asit expands, to provide a complementary surface structure to the nativeLAA wall to further enhance anchoring and promote sealing. Thus, theexpandable foam implant described herein conforms to the nativeconfiguration of the LAA. In one embodiment, the structure of the foammay be fabricated such that squeezing axially on the opposing ends ofthe foam causes the foam to increase in diameter.

The ePTFE or foam material may be provided with one or two or moreradiopaque markers such as radiopaque threads 210 or be filled with orimpregnated with a radiopaque filler such as barium sulfate, bismuthsubcarbonate, or tungsten which permit the operator to see under x-raythe plug for proper positioning in the anatomy. An x-ray image is shownin FIG. 3 where one cannot see a foam plug 300 but can clearly seethreads 302 and a crimp 304 (discussed below). This thread 302 or ribbonmay be made from a radiopaque metallic wire or tube such as platinum,platinum-iridium or tungsten or a polymer with a radiopaque filler suchas barium, bismuth, tantalum, tungsten, titanium or platinum.

An outer ePTFE layer may be formed from a tube with a diameter about thesame diameter of the foam plug and a wall thickness between about0.0001″ and about 0.001″ thick and serves to allow one to collapse andpull on the plug 204 without tearing the foam material. The ePTFEmaterial also serves as the blood contacting surface facing the LA 206and has pores or nodes such that blood components coagulate on thesurface and an intimal or neointimal covering of tissue grows across itand anchors tightly to the material. Pore sizes within the range of fromabout 4μ to about 110μ, ideally 5-35μ are useful for formation andadherence of a neointima.

The outer covering 206 may be constructed of materials other than ePTFEsuch as woven fabrics, meshes or perforated films made of FEP,polypropylene, polyethylene, polyester or nylon. The covering 206 shouldhave a low compliance (non-elastic), at least longitudinally, besufficiently strong as to permit removal of the plug, a low coefficientof friction, and be thromboresistant. The outer covering 206 serves as amatrix to permit plug removal as most foams are not sufficiently strongto resist tearing when pulled. The plug 204 can also be coated with orcontain materials, such as PTFE. Such materials may enhance the plug's204 ultrasonic echogenic profile, thromboresistance, and/or lubricity.The plug 204 can also be coated with or contain materials to facilitateechocardiographic visualization, promote cellular ingrowth and coverage.

The outer covering 206 has holes in it to permit contact of the LAAtissue with the foam plug 204 to encourage ingrowth of tissue into thefoam plug pores and/or allow blood flow therethrough. These holes may be1 to 5 mm in diameter or may also be oval with their long axis alignedwith the axis of the foam plug, the length of which may be 80% of thelength of the foam plug and the width may be 1-5 mm. The holes may be aslarge as possible such that the outer covering maintains sufficientstrength to transmit the tensile forces required for removal. The holesmay be preferentially placed along the device. In one embodiment, holesare placed distally to enhance tissue ingrowth from the LAA wall.

In one implementation, the implant is provided with proximal and/ordistal end caps of ePTFE, joined together by two or three or four ormore axially extending strips of ePTFE. The axially extending strips arespaced apart from each other circumferentially, to provide at least twoor three or four or more laterally facing windows through which the opencell foam body will be in direct contact with the tissue wall of theLAA. This outer covering could be a mesh or netting as well. As shown inFIG. 20, the covering 2004 is only on the proximal and distal faces ofthe plug 2000. They may be glued to the foam plug and then crimped tothe center tube 2002.

The implantable plug 204 or devices 10, 1020, 3000 (as described below)may be anchored and secured in place in the LAA by tissue ingrowthand/or with additional anchoring features. In some embodiments, the plug204 or devices 10, 1020, 3000 may be anchored by tissue ingrowth alone.

In some embodiments, other anchoring means may be implemented. One meansof adhering the foam plug in place within the LAA is to use an adhesive,such as a low viscosity cyanoacrylate (1-200 cps). The adhesive isinjected into place along the sidewall near the distal end of the foamplug 208. Holes in the ePTFE covering permit the adhesive to interactbetween the foam plug 204 and the LAA wall 200. Injection of theadhesive may be accomplished with several means, one of which is toinject through the catheter into the center lumen 212. Passages 214serve to guide the adhesive to the correct location. The distal end ofthe foam plug may be restricted at that time to prevent the adhesivefrom exiting the distal crimp 216. Alternatively, FIG. 21 shows tubes2104 that are pre-placed through the guide catheter 2102, through thecenter lumen of the plug 2106 and bend backwards in the LAA to thedistal end of the plug 2100. These tubes 2104 pass all the way to theproximal end of the guide catheter 2102 where a fitting is attached topermit injection of the adhesive which then exits the small tubes 2104at the desired location of the plug. These tubes are made ofpolyethylene, polypropylene or FEP so that the adhesive will not adhereto the tubes. The tubes 2104 are withdrawn after injection through theguide catheter out of the patient.

Other one part adhesives including aqueous cross linking adhesives,polyurethane, PEG, PGA, PLA, polycaprolactone or a lycine-derivedurethane may be used. In addition, these adhesives may be made in twocomponents such that one component is adherent to the foam and thesecond injected in vivo. Also, these two component adhesives may beinjected simultaneously to mix in vivo to prevent fouling of injectiontubes.

An alternative anchoring means for plug 400 or device 3000, etc. is oneor two or more distal anchors as shown in FIG. 4. A wire 404 is passedthrough a center lumen 410 into the LAA and attached to the distal wallof the LAA. In this case, a screw wire 408 is threaded into the wall ofthe LAA 406. A closer detail of this is seen in FIG. 5 as screw 502 isshown embedded into the LAA wall 504 but not all the way through theepicardial surface 506.

Additional means of anchoring include the use of a plurality of hooks orbarbs or graspers to grab the distal wall and baskets, malecots, distalfoam plugs and Nitinol wire birds nests that open within the LAA andpush outward on the wall or engage the protrusions of the LAA. It may bedesirable to place the plug then engage the anchor as a secondary step.One such embodiment could include a multitude of nitinol wires with aball or catch welded proximal to the anchor tip. These could be gatheredwith the delivery catheter then released when the ideal plug positionhas been confirmed.

A cross section of one embodiment is shown in FIG. 6 with foam plug 600and the LA face 602 and the LAA face 610. The ePTFE material 604encapsulates the foam plug 600 and its open ends are connected with anattachment structure such as a wire, suture or tubular crimp 606 over aninner tube 608. The inner tube 608 may be made of an implant gradestainless steel such as 304 or 316 grades or a cobalt-chromium alloysuch as MP35n and the crimp 606 may be made of annealed 304 or 316stainless steel or a cobalt-chromium alloy such as MP35n. This crimpalso serves as an element which can be snared should the device need tobe removed.

Referring to FIG. 6, the tubular ePTFE layer 604 extends along an innerlayer 612 which lines the guidewire lumen, and everts out around theleft atrial face 602 to form outer layer 614. In some embodiments, thelayer 604 may cover the entire proximal face and/or part of thesidewall, such as the cover 3100 or the cover over proximal face 1064′,as further described herein. As further shown in FIG. 6, a first end 616of inner layer 612 is disposed concentrically within a second end 618 ofouter layer 614. The first end 616 and second end 618 are clampedbetween inner tube 608 and outer crimp 606. In this manner, the implantcan be encapsulated in a manner that presents a seamless left atrialface 602, and preserves the integrity of the guidewire lumen with innertube 608.

An embodiment of a technique for placement of an LAA occlusion device isshown in FIGS. 7 through 15. To close the LAA, the LA is first accessedfrom the venous system. One approach is to use a Brockenbrough-styleneedle to puncture the atrial septum to access the LA from the rightatrium (RA). The basic needle-puncture technique is performed obtainingvenous access typically via the right femoral vein. A Mullins sheath anddilator are then tracked over a 0.025″ or 0.032″ guidewire previouslyplaced in the superior vena cava (SVC). Fluoroscopic andechocardiographic imaging, such as transesophageal echo (TEE) orintracardiac echo (ICE), are typically utilized. If echo is notutilized, it is common to also place a pigtail catheter in the aorticroot to define the location of the aortic valve, a step not necessarywhen using echo.

Once the Mullins sheath and dilator are in the SVC, the guidewire isremoved and a trans-septal needle is placed through the dilator. Theneedle contains a stylette to prevent skiving off of polymeric materialfrom the dilator lumen as it traverses to the tip. Once the needle isnear the dilator tip, the stylette is removed and the needle isconnected to a manifold and flushed. The Mullins sheath/dilator set andthe needle (positioned within the dilator tip) are retracted into theSVC toward the RA as a unit. As the system is withdrawn down the wall ofthe SVC into the RA and positioned in the fossa ovale, the preferredpuncture location.

Once proper position in the fossa ovale is observed, the needle isadvanced across the fossa ovale into the LA. Successful trans-septalpuncture can be confirmed by echo, pressure measurement, O₂ saturationand contrast injection. Once the needle position is confirmed to bepositioned in the LA, the sheath and dilator can be advanced over itinto the LA. In some cases, the user will first pass a guidewire throughthe needle into the LA and into an upper pulmonary vein (typically theleft) prior to crossing. Alternative options include the use ofradiofrequency trans-septal needles, which are useful for crossing verythick or hypertrophic septa, or the use of a safety wire placed throughthe needle and utilized for the initial puncture.

Referring to FIGS. 8 through 15, a guide catheter 802 is placed throughthe femoral vein into the right atrium of the heart and across theintra-atrial septum into the LA as described above and positioned nearthe LAA ostium 804. A guidewire 902 usually of 0.035″ diameter is placedthrough guide catheter 900 and into the LAA 904. This guidewire 1002 mayhave attached to its distal end a balloon 1006 which is inflated in theLAA and serves as a bumper to prevent guide catheter 1100 fromperforating the wall of the LAA. The guide catheter 1100 is thenadvanced over the guidewire 1108 into the LAA 1104. A radiopaque marker1102 is used to guide catheter placement under fluoroscopy.

The foam plug 1204 is then pushed through the guide catheter 1200 withpusher 1202 and is shown exiting the guide catheter 1300 slowly in FIG.13 until it is fully deployed as shown in FIG. 14. The foam plug 1404position may then be adjusted in place using the distal balloon 1408 andthe guide catheter 1400, sliding the foam plug proximally by pulling onthe balloon 1408 through shaft 1412 or sliding it distally by pushingguide catheter 1400 distally. The guidewire may also contain a pressuresensor within it such that sealing of the LAA is monitored andconfirmation of a sufficient seal is made. Once the placement issatisfactory, the adhesive 1514 may be injected and/or mechanicalanchors be deployed anchoring the plug 1404 to the wall. The guidewireballoon 1508 is deflated, after which the guidewire is removed. In analternative embodiment, a binary adhesive system can be used where onecomponent of the binary system is bonded to the outer surface of theskin covering the foam plug. The second component can be injected at theinterface between foam plug and the wall of the LAA such that bondinghappens only at the interface minimizing the risk of adhesiveembolization. In some embodiments, adhesives and balloons may or may notbe used, for example with the device 3000 further described herein.

An alternative to pushing the plug through the entire length of theguide catheter is that the plug 1204 may be initially located at thedistal end of the guide catheter 1200 as shown in FIG. 12. The guidewire1210 passes through the center of the plug 1204 and in this mode, thepusher 1202 only needs to push the plug a short ways to deploy it intothe LAA.

For alternative anchors, they may be deployed, the shafts disconnectedand removed. Disconnection mechanisms may be any of several types, suchas threaded, electrolytic detachment, or others known in the art. Insome embodiments, a suture attachment may be implemented, for example asdescribed with respect to FIG. 24.

As shown in FIG. 16, in some embodiments, a foam body 1600 and metalframe such as stent 1602 may be included. The foam body 1600 and stent1602 may have the same or similar features and/or functionalities asrespectively the foam body 3002 and tubular body 3080 (see FIGS.85A-90D), and vice versa. The foam 1600 is designed to provide ingrowthof tissue and also to provide a cushion of the metal stent 1602 onto thetissue of the LAA. The proximal face 1604′ of the plug is covered inePTFE, polyester or another thromboresistant tissue scaffold material tofacilitate sealing with the desired pore size to encourage overgrowth.

The stent 1602 may be made of Nitinol to enable it to pack into a 10,12, 14, 16, 18 or 20 F delivery catheter and expand to its desireddiameter. The stent 1602 may be braided, laser cut or wire formed. Anyof a variety of stent wall patterns may be utilized, depending upon thedesired performance. The stent 1602 may be a balloon expandable stent,or self-expandable stent. In the illustrated embodiment, theself-expandable stent 1602 comprises a plurality of proximal apexes 1608and distal apexes 1610 connected by a plurality of zig zag struts 1612.A hole 1606 allows passage of the guidewire for delivery. This designmay be advantageous in that the expansion force exerted by the plug onthe LAA can be controlled separately from the foam characteristics.Also, it may be easier to pack this concept into a smaller geometry. Forexample, the plug can be packed into a smaller geometry by reducing theamount of foam that must be compressed into the delivery catheter whilemaintaining sufficient dilation force.

Alternatively, the foam plug may be constructed of two foams. One densercore to provide force, for example radial force, and an outer softerfoam to engage the tissue irregularities. The softer foam could also belocated on the proximal and/or distal ends to facilitate retrieval.

Another means of adding stiffness to the foam plug is shown in FIG. 17where a cavity 1704 in the foam plug 1700 is made and a coil of wire1702 may be advanced from the guide catheter at the proximal end 1706into the cavity 1704. As the wire enters the cavity, it expands to itspredetermined size and exerts force on the foam radially outwards. Thetype and amount of wire may be determined in vivo using x-ray guidanceto examine the radial expansion of the foam into the LAA.

Instead of wires as shown in FIG. 17, a balloon may be passed into thefoam and inflated to provide radial force while the outer foam serves toengage the tissue irregularities and tissue ingrowth. Followinginflation, the balloon may be detached from a deployment catheter andthe deployment catheter withdrawn. The balloon is preferably providedwith a valve, to prevent the escape of inflation media. Inflation mediamay be any of a variety of media which is convertible between a first,flowable state and a second, hardened state such as by cross linking orpolymerization in situ.

Another LAA plug is shown in FIG. 18 as a spring like implant wire 1800that is covered with foam 1802 to encourage ingrowth. The proximal faceof the implant is covered with a sheet of ePTFE or other tissuescaffolding material. This implant may be stretched out for delivery andreleased in place.

Rather than using a foam, a low porosity outer bag without perforationscould be placed in the LAA and then filled with a substance to providethe radial expansion. This substance may be a hydrogel, cellulose orpolyvinylacetate.

Rather than requiring the use of a separate dilation device to cross theseptum, the distal crimp element 1902 may be formed in a tapered mannersuch that it extends from the distal end of the catheter 1200 and servesas a dilating tip to dilate the opening in the septum as the catheter isadvanced. See FIG. 19.

An alternative plug design uses a foam such as cellulose sponge materialthat is compacted and dehydrated such that it can be packed into theguide catheter. This foam material 2202 may be packed into the guidecatheter as shown in FIG. 22. The foam plug 2202 is then advanced fromthe distal end of the guide catheter 2204 with a plunger 2206 into theLAA. The plug exits the guide catheter and opens to a disc shape 2210.As the foam absorbs fluid in the blood, its length expands to form acylinder 2220 filling the LAA. Expansion ratios for compressed cellulosematerials may be as high as 17:1, expanded to compressed length.

It may be advantageous to use small barbs 2302 in FIG. 23 to furtherengage the plug 2204 into the LAA. Barbs may be unidirectional orbidirectional to resist movement in either the proximal or distaldirection. These barbs are embedded into the foam plug and may be 0.1 to1 mm in height. It may be desirable to place the plug then engage thebarbs as a secondary step. One such embodiment could include a multitudeof nitinol barb wires with a ball or catch welded proximal to the barbtip. These could be gathered with the delivery catheter within a sleeveor suture then released when the ideal plug position has been confirmed.

One means of removing a device that is not functioning properly is toreleasably attach a retrieval suture 2400 to the implant, such as to theproximal cap 2402 which also passes proximally throughout the entirelength of the guide catheter 2404 in FIG. 24. If the device is to beremoved, pulling on both ends of the suture 2400 will pull the outercovering into the guide catheter 2404 which can then be removed from thepatient. If the device is properly placed, the suture 2400 may be cutand removed leaving the plug in place.

Deployment of the occlusion device has been discussed primarily in thecontext of a transvascular access. However, the implants mayalternatively be deployed via direct surgical access, or variousminimally invasive access pathways (e.g. jugular vein). For example, thearea overlying the xiphoid and adjacent costal cartilage may be preparedand draped using standard techniques. A local anesthetic may beadministered and skin incision may be made, typically about 2 cm inlength. The percutaneous penetration passes beneath the costalcartilage, and a sheath may be introduced into the pericardial space.The pericardial space may be irrigated with saline, preferably with asaline-lidocaine solution to provide additional anesthesia and reducethe risk of irritating the heart. The occlusion device may thereafter beintroduced through the sheath, and through an access pathway createdthrough the wall of the LAA. Closure of the wall and access pathway maythereafter be accomplished using techniques understood in the art.

Depending upon the desired clinical performance, any of the LAAocclusion devices described herein may be provided with a drug or otherbioactive agent, which may be injected via the deployment catheter, orimpregnated within the open cell foam or coated on the implant. Thebioactive agent may be eluted or otherwise released from the implantinto the adjacent tissue over a delivery time period appropriate for theparticular agent as is understood in the art. Useful bioactive agentscan include those that modulate thrombosis, those that encouragecellular ingrowth, throughgrowth, and endothelialization, andpotentially those that resist infection. For example, agents that maypromote endothelial, smooth muscle, fibroblast, and/or other cellulargrowth into the implant including collagen (Type I or II), heparin, acombination of collagen and heparin, extracellular matrix (ECM),fibronectin, laminin, vitronectin, peptides or other biologicalmolecules that serve as chemoattractants, molecules MCP-1, VEGF, FGF-2and TGF-beta, recombinant human growth factors, and/or plasma treatmentwith various gases.

Anti-thrombotics can typically be separated into anti-coagulants andanti-platelet agents. Anti-Coagulants include inhibitors of factor(s)within the coagulation cascade an include heparin, heparin fragments andfractions as well as inhibitors of thrombin including hirudin, hirudinderivatives, dabigatran, argatroban and bivalrudin and Factor Xinhibitors such as low molecular weight heparin, rivaroxaban, apixaban.

Antiplatelet agents include GP 2b/3a inhibitors such as epifibitide, andabciximab, ADP Receptor agonists (P2/Y12) including thienopyridines suchas ticlopidine, clopidogrel, prasugrel and tacagrelor and aspirin. Otheragents include lytic agents, including urokinase and streptokinase,their homologs, analogs, fragments, derivatives and pharmaceutical saltsthereof and prostaglandin inhibitors.

Antibiotic agents can include, but are not limited to penicillins,cephalosportins, vancomycins, aminoglycosides, quinolonges, polymyxins,erythromycins, tetracyclines, chloraphenicols, clindamycins,lincomycins, sulfonamides, their homologs, analogs, derivatives,pharmaceutical salts and combinations thereof.

Biologic agents as outlined above maybe be added to the implant 204 andmay be injected through the delivery catheter into the space between theproximal cap 206 and the foam plug 204. This may serve as a reservoir tominimize thrombus formation during the initial implantation and reducethe need for systemic anticoagulation following device implantation.

An electronic pressure sensor may be embedded into the proximal end ofthe foam plug which may be used to transmit LA pressure to a remotereceiver outside the body for the monitoring of LA pressure which isuseful to monitor cardiac function. In addition, a cardiac pacer ordefibrillator may be embedded into the foam plug and attachedelectrically to the distal anchor. A drug delivery reservoir may beembedded with connection to the LA for controlled delivery of biologicagents as outlined above.

Another means of anchoring is shown in FIG. 25A where the foam plug 2500is placed in the LAA. The distal screw lead 2502 is advanced and screwedinto the LAA wall. Guide 2506 is pulled proximally as shown in FIG. 25B.When this guide 2506 is pulled back, the screw lead wire, made ofNitinol, bunches up into a “birds nest” 2508 or forms a coil inside thefoam plug 2500. The screw lead wire 2502 is pushed distally from theguide catheter 2504 with a pusher 2510 and continues to bunch up intothe foam. The catheter system 2504, 2506 and 2510 are then removed.

Another means of anchoring the distal anchor element to the foam isshown in FIG. 26. Two barbed leads 2604 are attached to anchor 2602 suchthat when advanced into place in the foam plug 2600, the barbs 2604 diginto the foam plug.

FIGS. 27A-27G are various views of an embodiment of a device 10 forocclusion of the LAA (LAA). The device 10 may include the same orsimilar features as other devices for occlusion of the LAA describedherein, such as the plug 204, device 1020, device 3000, etc., and viceversa. The device 10 includes an internal locking system 101 forsecuring the device 10 within the LAA. In some embodiments, the device10 may not include the internal locking system 101 or other anchoringfeatures, for example the device 10 may be anchored by tissue ingrowthalone. The occlusion device 10 comprises an expandable media such as anopen cell foam body 15, for example a plug. The body 15 enables collapseand expansion of the device 10 and also enhances ingrowth of tissue intothe foam.

The body 15 of the device 10 shown in FIG. 27A through FIG. 27F is inits expanded configuration. The body 15 is in a compressed configurationin FIG. 27G. The device 10 includes the foam body 15, a skin 20, acentral lumen 25, a finial 30, and a dynamic internal locking system 101which anchors the device 10 within the LAA. FIG. 27A is a sidecross-section view of the device 10 showing the body 15 and the internallocking system 101 in a deployed configuration. FIG. 27B is an end viewof the proximal end of the device 10 showing the body 15 and theinternal locking system 101 in a deployed configuration. FIG. 27C is aside view of the device 10 showing the body 15 and the internal lockingsystem 101 in a deployed configuration. FIG. 27D is a side cross-sectionview of the device 10 showing the body 15 in a deployed configurationand the internal locking system 101 in a constrained configuration. FIG.27E is an end view of the distal end of the device 10 showing the body15 and the internal locking system 101 in a deployed configuration. FIG.27F is a cross-section view of the device 10 taken along the line 1F-1Fas shown in FIG. 27C. FIG. 27G shows the body 15 and internal lockingsystem 101 loaded and compressed within a delivery sheath 1. The device10 may be delivered via a delivery catheter in the configuration shownin FIG. 27G. The body 15 of the device 10 may then expand with theinternal locking system 101 still constrained, as shown in FIG. 27D. Theinternal locking system 101 may then deploy into the deployedconfiguration as shown in FIG. 27A.

FIG. 27G shows the body 15 and internal locking system 101 loaded andcompressed within an embodiment of a delivery sheath 1. In someembodiments, the delivery sheath 1 may be an outer delivery catheter.The body 15 and internal locking system 101 are loaded and compressedwithin a delivery catheter 5. The device 10 may be entirely or partiallyinside the delivery catheter 5. In some embodiments, the deliverycatheter 5 may be an inner delivery catheter. The device 10 may beloaded and compressed with the delivery catheter 5 inside of thedelivery sheath 1. Removing the delivery sheath 1, for example byretracting the delivery sheath 1 in the proximal direction, may allowthe body 15 of the device 10 to expand. The body 15 expands while theinternal locking system 101 is still constrained, for example by thedelivery catheter 5. FIG. 27D shows the body 15 in its deployed state,with the internal locking system 101 in a constrained configurationwithin the delivery catheter 5. This demonstrates the first step in thedeployment process, specifically placement of the device 10 within theLAA where the body 15 is expanded and the internal locking system 101 isconstrained and thus the anchors are not deployed. The second step ofthe deployment process is shown in FIG. 27A where the internal lockingsystem 101 has been deployed through the body 15. In some embodiments,this second step is reversible to retract the anchors, for example ifplacement of the device 10 within the LAA is unacceptable. The internallocking system 101, for example an anchoring component or system asfurther described herein, is deployed from within the body 15 to deployat least one and in some implementations at least 2 or 4 or 6 or moreanchors of the internal locking system 101 outside the body 15 to engageadjacent anatomy of the LAA.

The internal locking system 101 may be controllably deployed a period oftime after the body 15 expands. For instance, the location, orientation,etc. of the device 10 may be verified with various imaging techniquessuch as by fluoroscopy with injection of contrast media via the centrallumen before the internal locking system 101 is deployed and the anchorssecure the device 10 within the LAA. In some embodiments, even afterdeployment of the internal locking system 101 and anchors thereof, theanchors may be retracted to a position within the body 15 forrepositioning, and/or retrieval of the device 10 from, within the LAA.

FIG. 27F shows an embodiment of the device having slots 17. The slots 17are formed within the foam body 15. For instance, material of the foambody 15 may be removed to facilitate deployment of the internal lockingsystem 101, such as outward expansion of anchors to engage the tissue.

The device 10 may have any or all of the same or similar features and/orfunctionalities as the other plugs described herein, for example theplug 204, etc. For example, the device 10 is at least partiallyencapsulated within the skin 20. In some embodiments, the skin 20 maycover the proximal end of the body 15. The skin 20 may be a thin, strongouter layer. The skin 20 may be a thin, encapsulating layer. The skin 20may be fabricated from ePTFE (expanded polytetrafluoroethylene),polyolefin, polyester, other suitable materials, or combinationsthereof. In some embodiments, the skin 20 may be fabricated frombioabsorbable materials, for example polylactic acid (PLA), Polyglycolicacid (PGA), ploycaprolactone (PCL), PHA, collagen, other suitablebioabsorbable materials, or combinations thereof. The skin 20 can beoriented or otherwise modified to be elastomeric in at least onedirection, such as radially.

The body 15 may be made of polyurethane, polyolefin, PVA, collagen foamsor blends thereof. One suitable material is a polycarbonate-polyurethaneurea foam with a pore size of 100-250 um and 90-95% void content. Thebody 15 may be non-degradable or use a degradable material such as PLA,PGA, PCL, PHA, and/or collagen. If degradable, the tissue from the LAAwill grow into the foam body 15 and replace the foam over time. The body15 may be cylindrical in shape in an unconstrained expansion, but it mayalso be conical with its distal end smaller than the proximal end, orvice versa. The body 15 may also be oval in cross section to bettermatch the opening of the LAA.

The device 10 is oversized radially in an unconstrained expansion to fitsnuggly into the LAA. The device 10 may be 5-50 millimeters (mm) andgenerally at least about 10 mm or 15 mm in diameter in its unconstrainedconfiguration, for example depending on the diameter of the target LAA.The length “L” of the device 10 may be less than, similar to or greaterthan its diameter “D” such that the L/D ratio is less than 1.0, about orgreater than about 1.0, greater than about 1.5, or greater than about2.0. The L/D ratio may be greater than 1.0 to maximize its stability.However, in some embodiments, the L/D ratio may be less than 1.0, forexample, from about 0.2 to about 0.9, or from about 0.3 to about 0.8, orfrom about 0.4 to about 0.6. The compliance of the material of thedevice 10 is designed such that it pushes on the walls of the LAA withsufficient force to maintain the plug in place but without overlystretching the LAA wall. The foam body 15 and/or skin 20 also conformsto the irregular surfaces of the LAA as it expands, to provide acomplementary surface structure to the native LAA wall to furtherenhance anchoring and promote sealing. Thus, the expandable foam body 15conforms to the native irregular configuration of the LAA. In someembodiments, the structure of the foam body 15 may be fabricated suchthat axial compression on the opposing ends of the body 15 such as byproximal retraction of a pull wire or inner concentric tube causes thefoam to increase in diameter.

The body 15 and/or skin 20, for example the foam material and/or ePTFE,may be provided with one, two or more radiopaque markers, such asradiopaque threads 210 (see FIG. 2) or filled with or impregnated with aradiopaque filler such as barium sulfate, bismuth subcarbonate, ortungsten, which permit the operator to visualize under x-ray the device10 for proper positioning in the anatomy. Visualization of the device 10may be used to verify the position of the device 10 before deployment ofanchors to secure the device 10 in place.

The skin 20, such as an outer ePTFE layer, may have a thickness betweenabout 0.0001 inches and about 0.0030 inches. In some embodiments, thethickness of the skin 20 may be between about 0.0003 inches and about0.0020 inches. In some embodiments, the thickness of the skin 20 may bebetween about 0.0005 inches and about 0.0015 inches. The thickness ofthe skin 20 may be uniform, for example the same or approximately thesame no matter where the thickness is measured. In some embodiments, thethickness of the skin 20 may be non-uniform, for example the thicknessmay be different in different portions of the skin 20.

The skin 20, such as an outer ePTFE layer, may also serve as the bloodcontacting surface on the proximal end of the device 10 facing the LA.The skin 20 may have pores or nodes such that blood components coagulateon the surface and an intimal or neointimal covering of tissue growsacross it and anchors tightly to the skin material. Pore sizes may bewithin the range of from about 4μ to about 110μ. In some embodiments,the pore sizes are within the range of from about 30μ to about 90μ. Insome embodiments, the pore sizes are within the range of from about 30μto about 60μ. Such ranges of pore sizes are useful for formation andadherence of a neointima. In some embodiments, the skin 20, such as anouter ePTFE layer, may be formed from a tube with a diameter about thesame diameter of the foam body 15. and allows one to collapse and pullon the body 15 without tearing the foam material.

The skin 20 may be constructed of materials other than ePTFE such aswoven fabrics, meshes or perforated films made of FEP, polypropylene,polyethylene, polyester or nylon. The skin 20 may have a low compliance(e.g. non-elastic), for instance a low compliance longitudinally, may besufficiently strong as to permit removal of the plug, may have a lowcoefficient of friction, and/or may be thromboresistant. The skin 20serves as a matrix to permit plug removal as most foams are notsufficiently strong to resist tearing when pulled. The body 15 can alsobe coated with or contain materials to enhance its ultrasonic echogenicprofile, thromboresistance, lubricity, and/or to facilitateechocardiographic visualization, promote cellular ingrowth and coverage.

The skin 20 may include holes to permit contact of the LAA tissue withthe foam body 15. Exposure of the foam body 15 to the LAA or othertissue has benefits for example encouraging ingrowth of tissue into thefoam plug pores and/or increasing friction to hold the body 15 in place.These holes may be 1 to 5 mm in diameter or may also be oval with theirlong axis aligned with the axis of the foam plug, the length of whichmay be 80% of the length of the foam plug and the width may be 1-5 mm.The holes may be as large as possible such that the outer coveringmaintains sufficient strength to transmit the tensile forces requiredfor removal. The holes may be preferentially placed along the device 10.In some embodiments, the holes are placed distally to enhance tissueingrowth from the distal LAA wall.

In some embodiments, the device 10 includes an occlusion region andanchoring region. The proximal portion of the device 10 facing the LAafter the device is implanted in the LAA may include the occlusionregion. The occlusion region may be a blood contacting surface on theproximal end of the device 10 that is thromboresistant while promotingformation of a neointima at the occlusion region. The occlusion zoneencourages thromboresistance and endothelialization from the blood andadjacent tissue. The anchoring zone promotes fast and tenacious tissueingrowth into the device 10 from the adjacent non-blood tissue. Theanchoring zone may be lateral surfaces of the device 10 that interfacewith tissue adjacent and/or within the LAA. The anchoring zone can alsoinclude the distal end of the device 10 that faces the distal wall ofthe LAA after implantation.

FIGS. 28A-28D are various views of an embodiment of an internal lockingsystem 101 that may be used with the device 10. In some embodiments,multiple internal locking systems 101 may be used with the device 10.FIG. 28A is a side view of the internal locking system shown in adeployed configuration. FIG. 28B is an end view of a distal end of theinternal locking system 101 in a deployed configuration. FIG. 28C is aside view of the internal locking system 201101 in a constrainedconfiguration. FIG. 28D is a side view of an embodiment of an anchor 120of the internal locking system 101.

Any of a variety of structures may be utilized as the dynamic internallocking system 101 with the device 10. In general, at least about two orfour or six or more tissue anchors 120 may be actively or passivelyadvanced from the implantable device 10 into adjacent tissue surroundingthe implantation site. Following deployment of the device 10 andexpansion of the body 15, a tissue engaging segment 121 of the tissueanchor 120 will extend beyond the skin by at least about one, and insome implementations at least about two or four 4 mm or more. The tissueengaging segment 121 is carried by a support segment 122 of the tissueanchor 120 which extends through the foam body 15, and may be attachedto a deployment control such as a pull wire, push wire, tubular supportor other control structure depending upon the desired configuration.

The locking system 101 discussed primarily herein is a passivedeployment construction. Removal of a constraint allows the tissueanchors 120 to laterally self-expand to deploy into adjacent tissue.Self-expansion may be accomplished by constructing the tissue anchor 120using nitinol, Elgiloy, stainless steel or other shape memory or springbias materials. The constraint may be removed by proximal retraction ordistal advance until the tissue anchors 120 are no longer engaged by theconstraint, depending upon the construction of the locking system 101.

Alternatively, tissue anchors 120 may be deployed actively such as bydistal advance, proximal retraction or rotation of a control, orinflation of a balloon positioned within the device 10 to actively drivethe anchors 120 through the skin 20 or corresponding apertures on theskin 20 and into tissue. For example, a plurality of support segment122, such as struts, may be joined at a distal end to a central hub 111,and incline radially outwardly in the proximal direction. Proximalretraction of the hub 111 will cause the tissue engaging segment 121 toadvance along its axis beyond the skin 20 and into the adjacent tissue.The inclination angle of the support segment 122, for example thestruts, may be reversed, in another construction, such that distaladvance of the hub 111 will deploy the tissue engaging segments 121beyond the skin 20. Proximal or distal advance of the hub 111 may beaccomplished by proximal or distal advance of a control such as acontrol wire or inner tube releasably engaged with the hub 111.

Depending upon the desired clinical performance, the tissue anchors 120may be retractable, such as by axial distal or proximal movement of thecontrol depending upon the inclination angle of the anchors 120. In theembodiment primarily illustrated herein, re-sheathing the anchors 120may be accomplished by advancing the tubular constraint along the rampedsurface of the tissue anchor 120 to move the anchor 120 radiallyinwardly towards the central longitudinal axis of the device 10. In thecase of an anchor 120 which deploys by advance along its ownlongitudinal axis, the anchor 120 may be retracted by advancing thecontrol in the opposite direction from the direction advanced to deploythe anchors 120.

Referring to FIGS. 28A-28D, the internal locking system 101 includes acentral tubular element or hub 111 and anchors 120. The anchors 120 maybe arms, segments, or other members extending from the hub 111. Eachanchor 120 may comprise a tissue engaging segment 121 and a supportsegment 122 which extends to the hub 111 or other control. The internallocking system 101 has a single central tubular hub 111 and a multitudeof the anchors 120. As shown, there are four anchors 120. There may betwo, three, four, five, six, seven, eight, or more anchors 120. Theanchor 120 may be rotatably, hingedly, or otherwise moveably coupledwith the hub 111. The anchor 120 may thus move relative to the hub 111,for example after being released from a restraint holding the anchor 120in a constrained configuration to deploy into a deployed configuration.As further example, the anchor 120 may move from the deployedconfiguration to a retracted position, as further described herein. Theanchor 120 may be curvilinear as shown, for example to allow the anchor120 to take the geometry shown in FIG. 28A when unconstrained.

The illustrated anchor 120 may have a distal region 130, a hinge region135, and/or a proximal region 125. The distal region 130 interacts withthe hub element 111. The hinge region 135 and the curvilinear geometryas shown allow the end of the proximal region 125 to extend beyond thebody 15, for example beyond a sidewall of the body 15. The proximalregion 125 includes a tissue engaging segment 121 configured to engageadjacent tissue. The tissue engaging segment 121 may be the entireproximal region 125 or a portion thereof, for example the tip, etc. Theproximal region 125 may thus include a sharpened tissue engaging segment121, a shaped tissue engaging segment 121, an angled tissue engagingsegment 121, a thickness configured for tissue engagement, and/or othersuitable features. In some embodiments, the proximal region 125 mayretract back within the body 15, as further described herein. In theembodiment shown, the anchor 120 and central tube 111 are distinctelements which are affixed to one another as shown. In otherembodiments, the anchor 120 and tube 111 are a single, integral unit.

The internal locking system 101 is made from biocompatible metallic wiresuch as Nitinol, implant grade stainless steel such as 304 or 316, orcobalt-chromium based alloys such as MP35N or Elgiloy. In someembodiments, the internal locking system 101 may be cut from a singletubular piece of metal fabricated via machining or laser cuttingfollowed by a secondary forming or annealing step using similarmaterials.

The internal locking system 101 may be in a constrained configuration asthe device 10 is placed in position in the LAA and the body 15 expandstherein. Then, in a secondary step, the internal locking system 101locks or otherwise secures the device 10 in the LAA by engaging theanchors 120. If the position is not considered optimal, or if the device10 otherwise needs to be repositioned within and/or removed from theLAA, the internal locking system 101 and anchors 120 thereof can beunlocked and the device 10 repositioned and/or removed.

FIGS. 29A-29B are sequential side views of an axially movable loop typeunlocking mechanism that may be used with the device 10 to release thetissue anchors. FIG. 29A is a side cross-section view of the device 10showing the tissue anchors of internal locking system 101 in a deployedconfiguration. FIG. 29B is a side cross-section view of the device 10showing the tissue anchors in a retracted configuration. An embodimentof an unlocking system 140 is shown. The unlocking system 140 includes aring 145. The ring 145 may be moved over the anchors 120 to move theanchors 120 to retracted configurations. The ring 145 may be moved by apull rod 147. The ring 145 may be releasably attached to the pull rod147. The pull rod 147 may extend through a catheter to engage the ring145. The unlocking system 140 may be utilized if, after the internallocking system 101 is deployed, it is desirable to unlock the device 10from within the LAA in order to reposition and/or remove the device 10.

In the illustrated construction, deployment of the tissue anchors bydistal advance of the restraint enables reversible deployment, so thatsubsequent proximal retraction of the restraint will retract the tissueanchors. Alternatively, proximal retraction of the restraint to releasethe tissue anchors will irreversibly release the tissue anchors.

FIG. 30 is a side view of an embodiment of the device 10 having flexibleanchors 401. The device 10 shown in FIG. 30 may have the same or similarfeatures and/or functionalities as the other devices for excluding theLAA described herein, and vice versa. The device 10 may be in theconfiguration shown in FIG. 30 adjacent to or within an LA 201. Thedevice 10 in FIG. 30 includes the expandable body 15, such as an opencell foam body, which enables collapse and expansion of the device 10,and at least partially encased within the skin 20, which may be a thin,strong layer fabricated from ePTFE (expanded polytetrafluoroethylene),polyolefin, or polyester which assists with healing, anchoring, andretrieval. The device 10 may also be deployed, and, if desired,repositioned and/or retrieved, or the device 10 may be permanentlyfixated within the LAA by engaging an anchoring system, such as theinternal locking system 101, as described herein. The anchors 401, whichmay be metallic, may be fabricated from Nitinol. The anchors 401 may besmall diameter Nitinol wire approximately 0.001 inches to approximately0.010 inches in diameter. In some embodiments, the anchors 401 may beapproximately 0.0005 inches to approximately 0.020 inches in diameter.The anchors 401 may be deployed upon expansion of the body 15. Forexample, the anchors 401 may self-deploy upon deployment of the device10 from a delivery catheter. The anchors 401 may be relatively short andextremely flexible. The anchors 401 may be unable to penetrate thetissue or cause any anchoring immediately after deployment of the device10.

FIG. 31 is a side view of an embodiment of a device 10 for occlusion ofthe LAA having anchors 401 with tubes 500. The device 10 may bepositioned adjacent to or within the LA 201. The anchors 401 may beflexible anchors, or in some embodiments the anchors 410 may berelatively stiffer, as further described. The tubes 500 may bestationary or moveable tubes, as further described. In some embodimentsthe tubes 500 are hypotubes. The tubes 500 may be stainless steel,polyamide, or other suitable materials. The tubes 500 may surround acorresponding anchor 401, as further described.

In some embodiments, the anchors 401 may be fixed such that they do notmove axially. For example, the anchors 401 may have a portion, such as atissue engaging segment 121, of a fixed length extending outside thebody 15. The portion of the anchors 401 extending outside the body 15may be bent when compressed within a delivery catheter and/or sheath,and these portions of the anchors 401 may then straighten out to theconfiguration shown in FIGS. 31 and 32 after deployment of the body 15.The fixed length portion of the anchors 401 extending beyond the body 15may be from about 1 mm to about 5 mm, or from about 1.5 mm to about 4mm, or from about 2 mm to about 3 mm. This length of exposed anchor 401outside the body 15 may be effectively shortened by deployment of acorresponding tube 500, as further described. Deployment of thecorresponding tube 500 about the corresponding anchor 400 may shortenthe effective length of exposed anchor 401, i.e. the length of theanchor 401 extending beyond the end of the tube 500 after deployment ofthe tube 500, from about 0.5 mm to about 1 mm. These are merely examplesof different lengths of the anchor 401 and other suitable lengths may beimplemented.

In some embodiments, the anchors 401 may be moveable axially. Forexample, the anchors 401 may not deploy or otherwise extend outside thebody 15 immediately upon expansion of the body 15. Following acceptablepositioning of the device 10 within the LAA, the flexible anchors 401may then be advanced through a corresponding tube 500. The anchors 401may move axially in any suitable manner, including those describedelsewhere herein. The anchor 401 may be moved through the tube 500either before or after the tube 500 has been moved and deployed outsidethe body 15, as described below.

In some embodiments, the tubes 500 are moveable and deploy outside thebody 15. The tubes 500 may be moveable in embodiments having eitherfixed or moveable anchors 401. The tubes 500 may be pre-loaded overcorresponding wire anchors 401 as shown in FIG. 31, for example one tube500 per anchor 401. The tube 500 may then be moved over thecorresponding anchor 401 as shown in FIG. 32. The tube 500 maystraighten the anchor 401 and add mechanical integrity. The tube 500 mayalso act as a perforation protector to prevent the anchor 401 frompuncturing through the wall of the LAA. Movement of the tube 500 overthe corresponding anchor 401 may shorten the exposed length of theanchor 401, as described. This may provide for a stiffer tissue engagingsegment of the anchor 401 due to the shortened exposed length.

In some embodiments, the tubes 500 extend from the delivery catheter toor near the outer surface of the body 15 but do not extend outside thebody 15. Instead, the tubes 500 just guide the anchor 401, for examplearound the curve, and support the wire 401 right up to tissuepenetration. The tubes 500 may set the launch angle so the anchor 401does not buckle and hits the tissue at the right angle. In thisembodiment, the anchor 401 may have relatively more stiffness than inthe embodiments where the anchors 401 are relatively flexible, in orderto provide a more secure anchoring of the device 10 to the tissue. It isunderstood the tube 500 may provide this guiding function to thecorresponding anchor in any of the embodiments described herein havingmoveable anchors, such as the moveable anchors 401, the anchors 120,etc.

The flexible anchors 401 and/or the external stiffening tube 500 may bemade from biocompatible metallic materials such as Nitinol, implantgrade stainless steel such as 304V or 316LVM, cobalt-chromium basedalloys such as MP35N or Elgiloy, other suitable materials, orcombinations thereof. The anchor 401 length can vary from 0.1 mm to 5 mmin length with an external stiffening tube 500 that covers from 10% to90% of the exposed length of the anchor 401.

The skin 20 at least partially surrounds the body 15 and portions of theskin 20 may or may not be attached to the body 15. The various devices10 described herein may have the body 15 at least partially encasedwithin the skin 20, which may be fabricated from a material such asePTFE (expanded polytetrafluoroethylene), polyolefin, or polyester whichassists with healing, anchoring, and retrieval. FIG. 33 is a side viewof an embodiment of a device 10 for occlusion of the LAA having discretepoints of attachment 700 of the skin 20 to the internal foam body 15.For clarity, the points of attachment 700 are shown as dots in thefigures. It is understood the points of attachment 700 may not bevisible from outside the device 10, for example the skin 20 may bebonded to the body 15 at the points of attachment 700, etc. In someembodiments, in addition or alternatively to bonding, the skin 20 may besecured for example with sutures to the body 15 at the points ofattachment 700, and thus some or all of the points of attachment 700 maybe visible from outside the device 10. The device 10 may be in theconfiguration shown in FIG. 33 adjacent to or within the LA 201. Theskin 20 may be attached to the body 15 at the various separate points ofattachment 700. As shown in FIG. 33, the skin 20 can be partiallyattached, with portions thereof not attached at all, to the body 15.This may allow, for example, the skin 20 to move during expansion of thebody 15 that occurs after deployment of the device 10 from the deliverycatheter. The skin 20 may, in some embodiments, be attached at points ofattachment 700 located near the proximal side of the device 10, forexample to help promote closure of the ostium of the LAA, such as with arim 800 as described below. The skin 20 may, for example, be tacked inplace in one or more points of attachment 700 near the proximal face sothat any bunching of the skin 20 that occurs during implantation occursnear the ostium but within the LAA. This can be achieved using sutures,adhesive bonding, heat bonding, other suitable approaches, orcombinations thereof.

The selective location of the points of attachment 700 may facilitatewith formation of a circumferential rim 800 of the skin 20. The rim 800is shown schematically in FIG. 34 as a triangular rim for clarity. It isunderstood the rim 800 may be a variety of different shapes depending onthe configuration of the device 10, the shape of the LAA, etc. Further,the rim 800 may extend completely or partially around the device 10. Therim 800 may surround the ostium of the LAA. The formation of the rim 800may help to completely seal the entrance to the LAA around the device 10and thereby prevent leakage. The attachment points 700 between the skin20 and the body 15 can prevent irregular bunching of the fabric andinstead guide any excess material to form the sealing rim 800 around ornear the proximal face of the device 10, as shown in FIG. 34. The rim800 may form upon expansion of the body 15 after deployment from thedelivery catheter, as described herein. Alternatively the attachmentpoints 700 can be designed so as to prevent any bunching at all of thefabric and provide a smooth surface, such as a smooth proximal surface.

FIGS. 35-36 are side views of embodiments of the device 10 havinganchors 120 with V-tips 901 shown in the deployed configuration. TheV-tips may be located in the proximal region 125 and/or may form all orpart of the tissue engaging segment 121 of the anchor 120, as describedherein. The V-tips 901 form a V-shaped point. The V-tips 901 aregenerally in the shape of a “V” or an otherwise angled, segmented shape.The V-tips 901 may be sharp barbs or hooks. The V-tips 901 may be formedfrom wire or laser-cut tubing or other suitable methods. As shown inFIG. 35, one or more of the V-tips 901 are attached to the body 15encased in the skin 20. The V-tips 901 can be attached to the body 15and/or to the skin 20. In some embodiments, the V-tips 901 are ends ofanchors 1000. For example, the V-tips 901 may be part of the anchors1000 that are within the body 15 and skin 20, as shown in FIG. 36. Thedistal ends of the V-tips 901 may be free to slide along and collapse orexpand. The distal ends of the V-tips 901 may be attached to the body15, skin 20, and/or the anchors 1000 to allow the V-tips 901 to collapseand retract. During retrieval into a catheter or sheath, the V-tips 901can flatten out when engaging the inner diameter of the catheter orsheath. The V-tips 901 can be formed from Nitinol, implant gradestainless steel such as 304 or 316, cobalt-chromium based alloys such asMP35N or Elgiloy, other suitable materials, or combinations thereof. TheV-tips 901 may then recover their pre-set shape after deployment orre-deployment.

FIGS. 37A-37C are side views of various embodiments of V-tips that maybe used with the anchors described herein. FIG. 37A is a side view of anembodiment of the V-tip 901. The V-tip 901 includes two angled segments.The segments may form the angle in a free state. The angle may bevarious angular amounts. In some embodiments, the angle formed by theV-tip 901 is no more than about 170°, 160°, 150°, 140°, 130°, 120°,110°, 100°, 90°, 80°, 70°, 60°, or any smaller, greater or intermediateangular amount. FIG. 37B is a side view of an embodiment of a wave V-tip1101. The wave V-tip 1101 may include a curved segment and an angledstraight segment. FIG. 37C is a side view of an embodiment of a two-waveV-tip 1103. The two-wave V-tip 1103 may include two curved segments. Thecurved segments may promote engagement of the tip with the inner wall ofthe LAA. The end of the various V-tips may be smooth and rounded orsharp to promote tissue penetration. In some embodiments, all of theV-tips may have the same shape. In some embodiments, some of the V-tipsmay have a first shape and other V-tips may have a second shapedifferent from the first shape. In some embodiments, some of the V-tipsmay be attached to the skin 20 and or body 15. In some embodiments, someof the V-tips may be attached to the anchors 1000.

FIG. 38 is a side view of another embodiment of the device 10 forocclusion of the LAA implanted inside an LAA 1201. The device 10includes a body 15 with a skin 20 and finial 30 placed within the LAA1201. The LAA includes a thicker proximal portion 1203 closer to theostium. The internal locking system 101, for example anchors thereof,may be configured to engage with the thicker proximal portion 1203 ofthe LAA. The various anchors, V-tips etc. described herein for thevarious embodiments of the device 10 may be used to secure the anchorsin the thicker proximal portion 1203. In some embodiments, the device 10may be deployed from the catheter such that the body 15 expands. Thelocation, orientation, etc. of the expanded body 15 within the LAA maybe verified, for example by imaging, as described herein. The location,orientation, etc. of the expanded body 15 within the LAA may be verifiedto ensure engagement of the internal locking system 101, for exampleanchors thereof, with the thicker proximal portion 1203. Then, theinternal locking system 101, for example anchors thereof, may bedeployed to engage the thicker proximal portion 1203. If afterdeployment of the internal locking system 101, for example anchorsthereof, it is determined that the anchors did not engage with thethicker proximal portion 1203, the anchors may be retracted, asdescribed herein, in order to reposition and/or retrieve the device 10.

In some embodiments, the internal locking system 101, for exampleanchors thereof, may be preloaded surface elements releasablyconstrained or otherwise locked down in a collapsed or constrainedposition or configuration. The internal locking system 101, for exampleanchors thereof, may be constrained using a restraint. The restraint maybe a dissolvable polymer, a lasso, or wires that can be retracted torelease the anchors. The restraint may be similar to a deadbolt. Otheranchoring concepts include Velcro integral to the ePTFE, electricallyorientable/ratcheting anchoring elements, unidirectional Gecko tape, orwires pre-attached to the finial 30. In some embodiments, the body 15with skin 20 may be secured within the LAA by texturing the body 15 andexposing the body 15 to the tissue through holes in the skin 20 toincrease the friction with the cardiac surface to a high enough level toprevent implant migration.

FIGS. 39A-39B are perspective views of an embodiment of a deployableanchor 1302 activated by a pull wire 1301 and shown, respectively, inthe constrained and deployed configuration, that may be used with thevarious devices 10, 1020, 3000 etc. for occlusion of the LAA describedherein. A two-stage anchoring system allows deployment of the anchors1302 after implantation and expansion of the body 15. This embodimentincorporates one or more hinged anchors 1302. The anchors 1302, which bea barb or other anchoring element, may lie flat during delivery andduring deployment of the body 15. Next, when pulled or pushed, theanchors 1302 bend at a hinge 1306 and extend outward from the surface ofthe body 15 and into the LAA tissue. The anchors 1302 may bend at thehinge 1306 using a hollow constraining element 1304 which can be a thin,metallic, round or rectangular box such as a round or rectangular shapedtube, and the pull wire 1301, for example a sliding element, which canbe a wire or suture. The pull wire 1301 is attached to the proximal endof the anchor 1302 and extends back through the delivery catheter orsheath. When the pull wire 1301 is retracted, the anchor 1302 slidesback though a slot 1308 in the tube 1304 and bends at the preformedhinge 1306. A portion of the anchor 1302 then extends out through theslot 1308.

FIGS. 40A-40B are perspective views of an embodiment of a deployableanchor 1405 activated by a lock wire 1401 and shown, respectively, inthe constrained and deployed configuration, that may be used with thevarious devices 10, 1020, 3000 etc. for occlusion of the LAA describedherein. The anchor 1405, which be a barb or other anchoring element, maybe formed from wire or a flat sheet of Nitinol or other shape memorymaterial and heat set to be in an expanded configuration. One or more ofthe anchors 1405 can be placed along the skin 20 or otherwise along anexternal surface of the body 15. One or more corresponding guides 1402,such as loops, may be located along the skin 20 or the body 15. Theguides 1402 may be located on both sides of the anchor 1405, as shown.The guides 1402 on a first side of the anchor 1405 may fix the anchors1405 in place. The guides 1402 on a second, opposite side of the anchor1405 may act as a guide for the lock wire 1401, which may be arestraining wire, suture, etc. The lock wire 1401 may be used toconstrain the anchors 1405 in a constrained configuration, for examplein the flat position as shown in FIG. 40A. When the lock wire 1401 isretracted, the anchors 1405 deploy, as shown in FIG. 40B. The anchors1405 may extend perpendicular to the body 15, or at an angle.

FIGS. 41A-41B are perspective views of an embodiment of a deployableanchor 1506 activated by a sheath 1502 and shown, respectively, in theconstrained and deployed configuration, that may be used with thevarious devices 10, 1020, 3000 etc. for occlusion of the LAA describedherein. The anchor 1506, which be a barb or other anchoring element, maybe formed from wire or a flat sheet of Nitinol or other shape memorymaterial and heat set to be in an expanded configuration.

One or more of the anchors 1506 may be placed along the skin 20 orotherwise along an external surface of the body 15. One or morecorresponding guides 1500 and locking loops 1504 may be located alongthe skin 20 or the body 15. The guides 1500 may be located on a firstside of the anchor 1506 and the locking loops 1504 may be located on asecond, opposite side of the anchor 1506, as shown. The anchors 1506 areheld in the constrained or restrained configuration or position by asheath cover 1502. The sheath cover 1502 may be tubular or rectangularin shape. The sheath cover 1502 constrains the anchors 1506. The sheathcover 1502 may constrain the anchors 1506 in a flat position as shown inFIG. 41A. When the sheath cover 1502 is retracted, the anchors 1506deploy, as shown in FIG. 41B. The anchors 1506 may extend at an angle tothe body 15, or perpendicularly.

FIGS. 42A-42D are various views of embodiments of the device 10 forocclusion of the LAA having external deployable anchors 1601, 1604 whichcan be collapsed and expanded by retraction into or out of a sheath orouter catheter. FIG. 42A is a side view of the device 10 having anchors1601 constrained by a delivery sheath 1603. FIG. 42B is a side view ofthe device 10 unconstrained by the delivery sheath 1603 with the anchors1601 deployed. FIG. 42C is a side view of the device 10 having anchors1604 constrained by the delivery sheath 1603. FIG. 42D is a side view ofthe device 10 unconstrained by the delivery sheath 1603 with the anchors1604 deployed. The body 15 with skin 20 can contain the anchors 1601 or1604 which are fixed to the surface of the skin 20 and are unconstrainedand therefore expanded in a free state, as shown in FIGS. 42B and 42D.The delivery sheath 1603, such as a catheter, may be used to constrainthe anchors 1601 or 1604. The anchors 1601 or 1604 may then expand whenthe body 15 is unconstrained by the delivery sheath 1603, for examplewhen the when the body 15 is released from the delivery sheath 1603. Theanchors 1601 may deploy into a curved shape as shown in FIG. 42B. Theanchors 1604 may deploy into an angled shape as shown in FIG. 42D. Theanchors 1603 or 1604 after deployment may point toward either theproximal or distal side of the body 15.

FIGS. 43A-43C are sequential side views of an embodiment of the device10 for occlusion of the LAA shown, respectively, constrained by a lasso1707, deployed, and adjusted with a mount 1705. One or more anchors 1709may be pre-mounted within the body 15 and attached distally to the mount1705. The mount 1705 may be a ring-like member having an openingextending therethrough. The mount 1705 is positioned over a rod 1701with end 1711. The mount 1705 can move, for example slide, over the rod1701 in the proximal direction. In some embodiments, the mount 1705 maybe pulled proximally, for example by a pull wire. In some embodiments,the mount 1705 may move when the rod 1701 is rotated. In someembodiments, the mount 1705 and/or end 1711 of the rod 1701 may bethreaded. Movement of the mount 1705 causes the anchor 1705 to move. Thedevice may include a tapered cone 1708. The cone 1708 may be attached tothe end of the rod 1701. The mount 1705 may be moved toward the cone1708 to adjust the height of the anchors 1709. Thus, the anchors 1709are angled more in FIG. 17C relative to FIG. 17B. The anchor 1709 maymove through the body 15 and into the tissue. The anchors 1709 may beadjusted to increase or decrease the amount of tissue penetration, forexample by moving the mount 1705 as described. For retrieval, thisprocess can be reversed. In some embodiments, the lasso 1707, attachedto a wire 1703, may extend, for example thread, through the threaded rod1701 and be placed around the anchors 1709 to retract the anchors 1709back into the body 15. In some embodiments, the lasso 1707 may be usedto initially constrain the anchors 1709 and then retract to allow theanchors 1709 to deploy.

FIGS. 44A-44C are side views of an embodiment of the device 10 forocclusion of the LAA having an adjustable two stage anchor system withanchors 1801 activated by moving a mount 1803 along a rod 1804. Theanchors 1801 may be internal grappling hook type structures placedwithin the body 15 and skin 20. The anchors 1801 may be introducedthrough a central lumen 1003 that extends through the body 15, as shownin FIG. 43A. The anchors 1801 may then travel through the body 15 andskin 20 to engage tissue, as shown in FIG. 43B. The anchors 1801 may beadjusted to increase or decrease the amount of tissue penetration. Theanchors 1801 are attached at distal ends to the moveable mount 1803. Themount 1803 is prevented from rotating, for example the mount 1803 may benotched to prevent rotation of the mount 1803 within the finial 30, asshown in FIG. 43C. The mount 1803 is threaded onto the threaded rod 1804that can be rotated clockwise or counter clockwise to change the linearposition of the mount 1803. The distal end of the rod 1804 may couplewith a cap 1807. The cap 1807 may rotate with the rotation of the rod1804. The mount 1803 may move proximally causing the anchors 1801 toextend past the surface of the body 15 and skin 20 as shown in FIG. 43B.The mount 1803 may move distally to pull the anchors 1801 back within orunder the surface of the skin 20. The depth of penetration of theanchors 1801 may be controlled, for example to account for thenon-circular cross-section of the LAA. In some embodiments, the anchors1801 may be deployed individually. Another option is to deploy theanchors 1801 distal to the body 15 with skin 20 and control thestiffness of the anchors 1801 such that they apply a reasonably uniformpenetrating force to the tissue at contact.

Various features for LAA (LAA) occlusion may be included, such as thosedescribed, for example, in U.S. patent application Ser. No. 15/290,692,filed Oct. 11, 2016 and titled DEVICES AND METHODS FOR EXCLUDING THELAA, in U.S. patent application Ser. No. 14/203,187, filed Mar. 10, 2014and titled DEVICES AND METHODS FOR EXCLUDING THE LAA, in European PatentApplication no. EP 14779640.3, filed Aug. 24, 2015 and titled DEVICESAND METHODS FOR EXCLUDING THE LAA, and in PCT Patent Application no.PCT/US2014/022865, filed Mar. 10, 2014 and titled DEVICES AND METHODSFOR EXCLUDING THE LAA, the entire disclosure of each of which is herebyexpressly incorporated by reference for all purposes and forms a part ofthis specification. Further additions and improvements to these andother concepts are described below. The embodiments described in thesections below may include the same or similar features and/orfunctionalities as the embodiments described above, and vice versa,except as otherwise noted or indicated by context.

A. Basic Plug Design Components and Improvements

Various occlusion devices and associated features are described withrespect to FIG. 45A to FIG. 77. The same or similar features and/orfunctionalities of the various devices as shown and described withrespect to FIG. 45A to FIG. 77 may be present in the various devices asshown and described with respect to FIGS. 1-44C and 78-93B, and viceversa.

As shown in FIGS. 45A-45C, the device 1020 (sometimes referred to hereinas “implant”) may utilize a cored-out foam “cup.” In some embodiments,this may be similar to the foam 1600 design shown in and described withrespect to FIG. 16 and/or the foam body 3002 described with respect toFIGS. 85A-93B. The “cup” design may be contrasted with a solid orgenerally solid tubular foam plug, such as those described and shown inFIGS. 2 and 6. Regarding the cup design of FIGS. 45A-45C, theapproximate thickness of the foam may be about 2.5 mm but can range fromabout 0.25 mm to about 10 mm. Note that the thickness may besignificantly thicker than the typical stent coating or covering asutilized in other applications (e.g. coronary stents, peripheral stents,AAA liners, etc.). In this application, where we are occluding, thethickness of the foam adds some desired structure between the gaps ofthe internal support structure 1032, such as a stent. In someembodiments, the thickness may be at least about 0.25 mm; in someembodiments at least about 0.50 mm, 0.75 mm, 1.0 mm or 2.0 mm or greaterin an unconstrained state, and in one implementation about 2.5 mm, withthickness selected depending upon the desired performance.

FIG. 45A is a cross-sectional view of the preferred embodiment showingthe components of the implant 1020 having a proximal (atrial) end 1022,a distal (LAA) end 1024 and an interior cavity 1026 in the expandedconfiguration. An expandable tubular wall 1028 defines the interiorcavity 1026, which may be enclosed at its proximal end 1022 by a tissuescaffold 1030 or other barrier configured to span the ostium and isolatethe LAA from the atrium post deployment. The proximal edge of thetubular wall 1030 may be provided with a ramped reentry or recapturesurface such as an annular chamfer 1031 extending circumferentially orotherwise around the proximal edge of the implant 1020, preferablycontinuously, to facilitate proximal retraction of the implant into thedeployment sheath to permit repositioning or removal if desired. Adistal extension 1029 of the tubular wall 1028 extends distally beyondthe internal support (discussed below) to form an atraumatic leadingedge.

The tissue scaffold 1030 may be integrally formed with the tubular wall1028 or may be bonded thereto. The tissue scaffold 1030 and the tubularwall 1028 may have approximately the same thickness and porecharacteristics, discussed below. Alternatively the tissue scaffold maycomprise a different material such as ePTFE, PTFE, Dacron, or othersknown in the art, configured to support tissue ingrowth and isolate theLAA, but thinner than the tubular wall 1028.

An expandable, internal support structure 1032 such as a wave stent 1034or other frame may be provided. The illustrated wave stent 1034comprises a plurality of struts 1038, adjacent pairs of struts joiningto form a plurality of proximal apexes 1041 and distal apexes 1042. Thestent 1034 may be laser cut from tube stock as is known in the art. Eachof at least three, and preferably at least 4 or 6 or 8 or more of theproximally facing apexes 1040 is provided with a reentry or recapturestrut 1044, which incline radially inwardly in the proximal direction toa central hub 1046. Recapture struts may be cut from the same tube stockas the stent. Hub 1046 may be provided with a central lumen, such as fordelivery over a guidewire, or for releasable engagement with adeployment device (not illustrated). Alternatively, the hub 1046 may beprovided with an attachment such as an eyelet 1048 for receiving asuture loop. A suture or other retention element may extend distallyfrom the deployment catheter, through the tissue scaffold 1028, throughthe eyelet 1048 and proximally back through the tissue scaffold 1028 andinto the deployment catheter. Following satisfactory positioning of theimplant 1020, the suture may be removed, releasing the implant 1020 fromthe deployment catheter leaving a homogeneous tissue scaffold 1030 asresilience of the material closes the suture tracks. In one preferredimplementation the implant 1020 is deployed from the delivery catheterwithout advancing over the wire and the hub lacks a central lumen. Inone embodiment, the implant is secured to the delivery system using anyof a variety of means known in the art including screw mechanisms orball in socket attachment mechanism, which can also pivot.

The tubular wall 1028 may be attached to the stent 1034 by adhesives,sutures or other bonding techniques known in the art. In the illustratedembodiment, the tubular wall 1028 is sutured to the stent 1034 and thetissue scaffold 1030 is sutured to the recapture struts 1044, with thesupport structure 1032 carried within the cavity 1026. Alternatively, atleast a portion of the support structure 1032 may be carried on theoutside surface of the tubular wall 1028 or tissue scaffold 1030. Thewave stent may be embedded within the tubular wall 1028 such as bysandwiching the stent between inner and outer layers of foam which arethen bonded together. Similarly the recapture struts may be enclosedbetween inner and outer polymer layers. The polymeric material can alsobe foamed around the stent so that a secondary attachment process is notrequired.

FIG. 45B is a distal end view of an embodiment of the implant 1020showing the internal metallic structure having a central hub 1046 andeight recapture struts 1044 inclining radially inwardly to the hub 1046.A plurality of suture retainers such as apertures 1050 are attached toor formed in the struts 1044 to receive the sutures used to secure thetissue scaffold 1030. This reduces the tendency of material of thetissue scaffold 1030 to slide distally along the struts 1044 if theimplant 1020 is proximally retracted into the deployment catheter.

The frame may be expandable from a contracted delivery configuration toan expanded deployed configuration. The frame may be retractable from anexpanded deployed configuration to a contracted delivery configuration.The frame may be generally tubular, e.g. circular, rounded, segmented,polygonal, other shapes, or combinations thereof in the unconstrained,expanded configuration, and preferably presses the foam into conformancewith the shape of the inside surface of the LAA. This permits thedeployed implant to minimize leaks, the largest of which is no more thanabout 4 mm or 3 mm or 2 mm or less and in some deployments essentiallyno leaks as viewed on color Doppler.

FIG. 45C is a proximal end perspective view of the outside of anembodiment of the implant 1020 having a unitary foam shell and showingthe proximal chamfer 1028, in an unconstrained expansion. Anchorsdeployed near the distal end of the frame are discussed in furtherdetail below.

Some advantages of the cored-out foam “cup”, as compared to a solid foamplug, are as follows: it still behaves like a full foam plug withrespect to conformability and sealing; it allows incorporation of aninternal metallic frame which can be optimized to provide the desiredamount of expansion for sealing and anchoring by providing an optimalradial force and an attachment point for the anchors, and a front faceinside the proximal face to aid in collapse of the foam for retrieval;by sizing the metallic frame so that it is shorter in length than thefoam cup, an atraumatic distal bumper is formed which is entirely foamand can be extruded from the sheath tip as the tip is advanced withinthe LAA; and the reduced overall volume of material aids with thefollowing: it significantly reduces the delivery profile, it is easierto flush to remove air prior to delivery into the vascular system, andit makes the plug more porous to blood so that if embolized within thecardiovascular system, it allows more blood to flow through it.

In an embodiment, the proximally facing edges of the foam plug 1040 arechamfered to aid in loading and retrieval. Also, while there can stillbe a central location to allow tracking of the implant 1020 over aguidewire-type device, in some embodiments there is no lumen or there isjust a slit in the foam plug 1040, as it is not desirable to have asignificant residual central hole which may cause thrombus formation orallow leakage. The slit can be a single slit, double cross-shaped slit,or multiple slits. The objective is to still allow tracking over aguidewire but to be sure the hole closes completely once the guidewireis removed. In the case of a solid face, the implant 1020 may not betracked over a guidewire and may instead, for example, be deliveredthrough a long transseptal sheath.

Please note that the term “guidewire”, as utilized above, can mean anactual medical device sold as a guidewire or it can be a catheter, suchas a pigtail catheter, which is initially placed in the LAA over whichthe LAAC (LAA Closure) implant 1020 is tracked.

Diameters: The LAA may vary in diameter from about 15 mm to about 33 mmand as such, the implant 1020 diameter must be able to accommodate thisvariation in sizes. The more the implant 1020 may accommodate variouslarge ranges of diameters, the fewer predetermined sizes are needed,thereby simplifying the procedure for implantation. The construct ofthis implant 1020 is such that it may accommodate diameters less than50% of the fully expanded diameter. The preferred plug 1040 diametersmay be about 27 mm, 33 mm, and 35 mm. Ideally, only 1-2 sizes would beneeded to close a large range of LAA diameters. This is a key advantageof the foam plug 1040 concept as compared to metal cage type deviceswith fabric tissue scaffolds.

Depth: The preferred plug 1040 length (the depth of the occluder withinthe LAA generally along a proximal-distal direction) is 20 mm and isindependent of the diameter of the implant 1020. This allows for goodimplant 1020 stability while still accommodating the majority ofanatomies. The distal tip of the foam plug 1040 is very soft, providingan atraumatic tip as it enters the LAA when the distal tip of theimplant 1020 is allowed to protrude past the distal dip of the deliverycatheter or sheath. The short depth makes placement of the plug 1040more robust, as there is less need to align delivery catheters with theLAA, as is needed with longer devices.

Foam and Porosity: The average pore size of the foam is 250-500 microns.The foam has a very high void content (90-95%) to promote quick andthorough tissue ingrowth. The open cell foam permits blood to flowthrough it. If the plug 1040 should embolize, it will be open enough toallow enough blood flow to be safe until it can be retrieved.Additionally, the large void content should be beneficial for properflushing of the implant 1020 to prevent air introduction into thevascular system. The porosity and cell size may be as described withrespect to the foam body 3002 of the device 3000, shown and describedfor example with respect to FIGS. 85A-90D.

The compliance and thickness of the foam are designed to provide a goodseal against the tissue with minimal compression. While other devicesrequire significant oversizing to obtain a seal, this implant 1020 mayrequire only <1 mm of oversizing.

LA Facing Surface: ePTFE (expanded Polytetrafluoroethylene) or PTFE asthe skin/layer for the implant 1020 such as over or partially over theplug 1040, as described above, may be ideal for supporting neointimalformation without thrombus formation. While embodiments may be describedwith respect to ePTFE, it is understood that PTFE may also be used. Itmay, however, reduce safety due to the inability or reduced ability toallow blood flow through the surface of an embolized implant 1020 due tothe low porosity of the ePTFE, even though blood flow may be enabledaround the outer surfaces of the cup. ePTFE porosity is much lower thanthat of the open cell foam, so blood flow across the membrane may benegligible. It is, however, hydrophobic which is beneficial forthromboresistance. One option, to maintain the desired open porosity ofthe foam structure while adding the thromboresistance of ePTFE and/orPTFE, is to add a PTFE coating via vapor deposition to the foam. Thethromboresistant coating may contain ePTFE or PTFE. This creates ahighly porous surface that simulates the ePTFE morphology. Methods ofattachment could include vapor deposition, as mentioned above orelastomeric glue (although this may eliminate porosity at the attachmentpoints). If ePTFE is preferred, that could be attached by encasing themetallic frame in ePTFE then wrapping through the center, around the OD,and attaching via sutures.

It may be desirable to reduce the pore size of the foam to between about30-200 um, as further described herein.

Barbs/Anchors: There are several options or types of barb designs thatmay be implemented for anchoring the implant 1020 within the LAA. Thefollowing are some examples: 1) Static: always engages tissue when theplug is deployed. This makes re-sheathing and repositioning of theimplant 1020 more difficult. 2) Constrained: the implant 1020 can bedeployed with barbs constrained. The implant 1020 can then berepositioned, as needed. The barbs are then released when the plug 1040is in its final position. 3) Dynamic: barbs can be deployed or retractedas desired without dislodging plug. Dynamic barbs may allow fordeployment and retraction, for example to reposition and/or remove theimplant 1020.

In some embodiments, the implant 1020 may have different features formother implants described herein. In some embodiments, the implant 1020may include any or all of the following features: does not have acentral lumen; has a spoked element against the proximal face inside thecup in addition to the wave stent; has anchors/barbs that can preferablybe activated as a secondary step following placement of the plug itself;has a layer on the proximal face, which may be similar to the proximalface 1604′ shown in FIG. 16 or the layer 3100 shown in FIG. 85A,although in some embodiments the PTFE may be applied via vapordeposition coating as opposed to expanded PTFE (ePTFE) attached as asecondary material.

B. Endoskeleton System with Proximal Spokes

The implant 1020 may include a foam plug 1040 with a centralendoskeleton that includes a proximal spoke face 1080 with severalradial struts. This configuration improves the ability to retrieve(re-sheath) the foam implant 1020. The stent version depicted in FIG.45A and FIG. 45B may be laser cut from a superelastic nitinol tube,however, numerous other biocompatible metallic materials can be utilizedsuch as shape memory Nitinol, stainless steel, MP35N, or Elgiloy. Whilethis embodiment is self-expandable, a balloon-expandable design could beutilized. Additionally the frame could be fabricated from drawn wire asopposed to being laser cut from a tube. Loops can be provided along eachstrut to allow for attachment to the foam via sutures, although otherattachment processes could be utilized, such as adhesive bonding. Theloops located mid strut can be oval in shape and staggered, to alloweasier loading into the delivery catheter and ease of fabrication.Additionally, as shown in FIG. 46, there may be no loops. While theembodiment shown in FIG. 45A has 8 struts, anywhere from 4 to 32 strutsmay be utilized. In general, it is preferred that the foam be attachedto the frame at numerous points including the center. This promotesretrieval without damage to the foam and the suture loops are beneficialfor this. In other embodiments, the foam could be formed around theendoskeleton so that it is within the foam, eliminating the need for asecondary attachment step. As shown in FIG. 45A, it is preferable thatthe proximal foam face have a chamfer at the edges to minimize the bulkof the material in this area to aid in re-sheathing.

FIGS. 47A-47B are perspective and side views respectively of anembodiment of the LAA occlusion device 1020 having an internal frame1032, which may be a single piece. While the design shown in FIG. 45B isfabricated from two separate pieces—the proximal spoke face 1080 witheight struts and a wave stent—in some embodiments there may be a singlepiece unit frame 1032, such as that shown in FIGS. 47A and 47B. In someembodiments the proximal spoke face 1080 may support re-sheathing, theeight crown wave cage stent 1060 supports the foam cylinder plug 1040,and the eight to sixteen, or fewer or more, barbs or anchors 1100located within the cylinder provide anchoring to resist embolization.The anchors 1100 can be located proximal, distal, and/or centrally alongthe length of the cylinder. The anchors 1100 can preferably range insize, when fabricated from a Nitinol tube, from about 0.003″ to about0.009″ in thickness and from about 0.007″ to about 0.015″ in width. Insome embodiments the anchors 1100 may extend about 1 mm from the surfaceof the implant 1020 but can range from extending about 0.5 mm to about 2mm, or less or more, from the surface of the implant 1020. The anchors1100 may be in a single location along the length of the cylinder orstaggered, as shown in FIG. 48. In vitro anchoring dislodgementresistance with these designs may be in the 0.5 lb to 1.5 lb forcerange. There may be a single row of anchors 1100 as shown. There may bemultiple

FIG. 49 depicts the implant 1020 with central endoskeleton that includesa proximal spoke face 1080 in its fully expanded configuration asattached to the delivery catheter. FIG. 50 depicts the implant 1020 inan embodiment of its collapsed configuration. Variations include anouter sheath component of the delivery catheter that can be stretchableor slit at the tip, aiding in tapering collapse. A reduced coefficientof friction on the foam face may reduce the forces required to collapsethe implant into the catheter. This may be done, for example, byapplying a layer of PTFE via vapor deposition or other processes to thefoam, or by a layer of expanded PTFE (ePTFE) attached to the proximalface using adhesives or mechanical methods such as suturing. Secureattachment of the foam face to the spoked system may be obtained bysuture attachment or other methods including adhesive bonding. whichwill prevent the foam from bunching up during retrieval which can resultin increasing forces and potentially tearing of the foam. If notsecurely attached with distributed forces, the metallic spoked elementmay pull through the foam during re-sheathing, destroying the implant.

C. Proximal (Blood-Contacting) Surface of the Foam

The foam implant 1020 may be comprised of porous open cell foam. Thefoam can be any of a variety of currently available materials includingpolyurethane-based biomaterials such as polyurethane orpolycarbonate-polyurethane, or polyvinyl acetal (PVA) (Ivalon®). Thefoam can also be reticulated, such as a net. An embodiment utilizes anon-resorbable reticulated polyurethane-based biomaterial. Additionally,resorbable foams could also be utilized including a polyhydroxyalkanoate(PHA) such as poly-4-hydroxybutyrate (P4HB) or cross-linked resorbablepolyester urethane-urea scaffolds.

Pore sizes in the material may be from about 50 micron to about 800micron, preferably from about 250 micron to about 500 micron. Such ahigh void content (e.g. from about 90% to about 95%) material promotesquick and tenacious tissue ingrowth and effectively mimics theextracellular matrix. While such a high void content material isdesirable for tissue ingrowth, it may not be ideal forthromboresistance, which is required for the left atrial (LA) surface. Athromboresistent surface is desired on the face that faces the LA. Ifmodifications are made to the LA facing surface to promote bloodcompatibility, those modifications may be extended from about 1 mm toabout 20 mm, preferably from about 1 mm to about 5 mm, onto the sides ofthe implant 1020 to assure thromboresistance in the event the implant1020 is deployed with a portion of the implant's 1020 side surfaceprojecting outside the LAA and into the blood environment. If there is ahole within the proximal face, such as a guidewire lumen, thethromboresistent surface may extend at least partially within thatlumen. Additionally, this thromboresistent layer should promote tissueingrowth and endothelialization.

Various methods may be used to create a thromboresistent proximal faceof the implant 1020, including but not limited to the following. Forexample, an expanded PTFE (ePTFE) skin or layer may be applied to theoutside surface of the foam implant as described elsewhere herein. Itcould be attached by encasing the metallic frame in ePTFE then wrappingthrough the center, around the OD, and attaching to the frame. This canbe done using numerous methods including suturing or adhesive bonding,including the use of elastomeric glue (although this may eliminateporosity at the attachment points). This ePTFE layer can extend into theguidewire lumen, if there is one. In addition to ePTFE, electrospun,melt blown, non-woven, knitted or woven fibers of PTFE, polyester, PGA,PLA, poly-4-hydroxybutyrate (P4HB) or other biocompatible fibermaterials can be utilized to create a porous biocompatible surface.

In some embodiments, a coating of a hydrophobic material such as PTFE isapplied over the proximal face using any of numerous processes known toone skilled in the art including vapor deposition coating. Ideally thiscoated layer would also extend partially onto the sides of the implant.While some embodiments may not include a guidewire lumen, if a centrallumen is present, the coating would preferably extend at least partially(e.g. about 1 mm) into it. To promote thromboresistance, this coatedlayer would decrease the porosity of the blood-contacting face to aporosity from about 30 microns to about 200 microns, preferably fromabout 100 microns to about 150 microns. Materials which could beutilized for this include conformal coatings such as PTFE applied in athickness of about 50-100 microns, polyurethane spray or dip coatings,albumin, polyethylene glycol (PEG), or poly(ethylene oxide) (PEO), allwith or without the incorporation of heparin or nitric oxide. The PEG orPEO would ideally be attached via a grafting process. In the preferredembodiment, the outer layer would also be lubricious to assist inre-sheathing of the implant. This can be achieved with both hydrophobicmaterials, such as ePTFE and PTFE, and hydrophilic ones, such as PEO andPEG. In order to produce a desirable combination of porosity and bloodcompatibility, a two-step process may be utilized where the foam isfirst coated with a base layer, such as a polyurethane-basedbiomaterial, then in a second step a more thromboresistent andlubricious surface is created utilizing PTFE, PEG, or PEO. Heparin orother anticoagulants may be added to the final blood-contacting surface.

Another option to create smaller pore sizes with an ePTFE-like materialwould be to attach an electrospun layer of PTFE to the face of the foamusing suturing. A very thin layer (<1 mm) can be made and attached viasuturing or adhesive bonding.

Another desired property of the foam of the plug 1040 is to provideechogenicity of the implant 1020, which allows for visualization byechocardiography. To promote echogenicity, a porous surface may beadequate; however, in certain cases a hydrophilic surface may bebeneficial. To promote blood compatibility and a hydrophilic surface,the preferred embodiment would be a foam implant which has a surfacegrafted with PEO or PEG.

D. Static Barb (Anchor) Designs

Static barbs engage tissue when the plug 1040 is deployed, e.g.expanded. While this simplifies fabrication, it makes re-sheathing andrepositioning of the implant more difficult.

In some embodiments, as shown in FIG. 51, a barb 2000 may be fabricatedfrom wire and crimped onto the stent 1034, in this example a wave stent.The barb may be made from Nitinol wire of any diameter, with a preferredrange of about 0.005″ to about 0.012″. The tip can be sharpened for easeof penetration into the tissue. It can be attached to the stent frameusing a crimp sleeve made from stainless steel, Nitinol, or titaniumtubing. It may require filler wires inside the crimp tube to preventrotation of the barb. It could also be attached by welding, using alaser or other energy source.

Referring to FIG. 52, in some embodiments a laser cut double barb 2000system can be utilized. This can be fabricated from a Nitinol tube 2002cut to allow two crimp ends with one barb 2000 near each crimp 2004 witha continuous Nitinol connection that follows the curvature of the stent1034, in this example a wave form. An advantage of this embodiment isthat it takes less labor to fabricate and shape the barbs, is easier tocreate sharp tips, and the curvature of the tube wall results instiffening the barbs. FIG. 53 shows an embodiment of the laser cut partof FIG. 52 prior to forming the crown curvature.

Referring to FIG. 54, in some embodiments the wire form follows thecurvature of the wave support cage 1034 (stent), terminating in twobarbs 2000. It can be crimped to the wave cage or can be sewn withsutures, welded, or glued in place on the wave cage (stent). Theadvantage is that crimping is not required to prevent barb rotation.

Referring to FIG. 55, in some static barb embodiments, a laser-cut wavesupport cage (stent) can be fabricated with integrated barbs 2000. Theadvantage of this concept is that no secondary attachment step isrequired to attach the barbs to the cage. It may also be easier to addmore barbs. A limitation is that it may be difficult to have 8 crowns(waves) with barbs on every strut as there may not be enough materialavailable, therefore 6 crowns may be preferable.

E. Constrained Barb (Anchor) Designs

With constrained barbs 2010, the implant 1020 can be deployed in the LAAwith the barbs 2010 constrained and can therefore be repositioned, asneeded, prior to barb release. The barbs 2010 are released when theimplant 1020 is in its final position.

In one embodiment, as shown in FIG. 56, a lasso-style constraint systemcan be added to static barbs to create constrained, deployable barbs2010. A suture material can be tucked between the barbs 2010 and strutsto prevent spinning upon deployment. Removal of the lasso can releasemultiple barbs in a circular array.

As shown in FIG. 57, barbs can be formed with a loop approximatelymidway along the barb 2010 which allows suture or thread to be placedthrough the loop, forming a lasso. This prevents full expansion of thebarbs 2010 until the body of the implant is in its final desiredposition within the LAA.

A flipping-barb option is shown in FIG. 58. In this embodiment, barbs2010 can be elongated designs that are folded back inside a cored-outfoam opening prior to loading into the delivery system. This may requiredrawstrings or other locking elements to hold the barbs in a constrainedconfiguration. Once the implant 1020 is in its final desired location,the constraint is removed and the barbs are no longer constrained andflip into position, engaging the tissue.

F. Dynamic Barb (Anchor) Designs

Dynamic barbs 2020 can be deployed or retracted as desired withoutdislodging the implant. Dynamic barbs 2020 may be the preferred optionfor some procedures, for example for recapture of the implant 102 intothe delivery catheter and/or sheath.

One embodiment is a tube within a tube. In this embodiment, as shown inFIG. 59, a laser cut tube 1030 may be utilized to construct a one-piecefront spoked face 1080 and wave stent 1032 from a single piece ofpreferably superelastic Nitinol tubing. Other materials, including shapememory Nitinol, stainless steel, MP35N, or Elgiloy, could be utilized. Asecond smaller laser cut tube 1040, as shown in FIG. 60, may be utilizedto form an inner spoked barb array.

As shown in FIG. 61, during deployment of the foam implant, the frontspoked face and wave stent may be deployed while the spoked barb arrayremains in a constrained position. The implant 1020 can be repositioned,as needed, then distal motion of the inner tube 1040 with respect to theouter tube 1030 allows the barbs 2020 to expand and engage, as shown inFIG. 62. The inner spoked barb array can be re-constrained andre-released repeatedly until disconnected from the delivery cathetertransmission lines.

In another embodiment, as shown in FIG. 63, a dynamic barb 2020 designwhich can preferably be fabricated from a single component isillustrated. This embodiment can be cut from a laser cut tube 1045,preferably superelastic Nitinol, where half of the front spokes connectto wave points of the stent cage 1032 to support re-sheathing while theother half of the spokes are formed into the barbs 2020.

Recapture or re-sheathing of the implant 1020 may initiate the barbretraction by collapsing the front spoke face, as shown in FIG. 64,thereby simultaneously retracting the barbs 2020 from the tissue. Thisallows for safe repositioning of the implant 1020 with a minimal amountof re-sheathing required (limiting the length of implant required to befully retracted into the sheath).

In another embodiment, as shown in FIG. 65, a dynamic hinged barb systemis illustrated. This is a laser cut wave form integrated barb 2020 witha living hinge and constraint. When the constrained end is heat-set, itmay curl inward to ride over or under the wave strut. When positionedover the wave strut, its sharp barb end may point to the inner diameterof the assembly. When popped into position under the strut, the opposingbarb end may see-saw upwards to engage tissue. Activation of the hingedbarbs 2020 can be accomplished through the use of a lasso threaded in acircular array between each barb and the corresponding strut. Cinchinginward on the lasso can pop the retention constraint from above thestrut to below the strut, causing the opposing barb end to be raisedabove the surface of the strut where it can engage a tissue surface.

G. Embodiments with Foam Cup, Wave Stent, and ePTFE Layer

As shown in FIGS. 66A-66C, the foam cup plug 1040 with internal wave orzig-zag anchor (for example, as shown in and described with respect toFIG. 16) can be modified to be completely covered on the outer surfaceby an ePTFE layer 2060. This layer 2060 can attach to the distal end1024 of the foam via suture or adhesive bonding as opposed to just theproximal face 1022. It can wrap over the entire external surface andinto the central lumen on the proximal face, attaching to the proximalportion of the wave stent by lamination or adhesive bonding. Otherbiomaterials or coatings could be utilized including, but not limitedto, PTFE or polyurethane.

H. Dynamic and Static Anchor Concepts

The embodiment of an implant 2300 shown in side cross-section view andend view in FIG. 67, respectively, includes anchors 2310 that can betied, welded, or crimped together at their proximal ends. The anchors2310 may be made of Nitinol wire to permit loading into the deliverysystem without taking a set. There could be 8-16 wires formed in thecurve. The anchors may act like a “grappling hook”. The assembly isloaded into the delivery catheter in a straightened position. As theyare pushed out of the delivery catheter, they take the shape shown inFIG. 67 and pierce into the tissue through the foam 2320. The foam 2320is cored out as shown to reduce the volume of foam needed to compressinto the delivery system and yet maintain sufficient radial force toseal the tissue.

The embodiment of the implant 2350 shown in FIGS. 68A and 68B includes awave stent internal anchor with barbs within a foam plug which has beencored out to be thicker on the distal end to create a larger atraumaticfoam tip bumper 2360 when collapsed within but partially deployed fromthe delivery catheter. The proximal face 2363 can have an internal lumen2365 as shown in FIG. 68A, but may not include an internal lumen asshown in FIG. 68B.

I. Constrained Anchor Deployed in Secondary Step

The embodiment of an implant 2370 shown in FIG. 69 has barbs/anchors2371 pre-attached to a wave stent 2372 inside the foam 2374. A suture2375 is looped around the distal end of the wave stent 2372 to compressthe stent 2372 and pull the barbs 2371 inward. The suture 2375 is tiedwith a slip knot. After delivery of the device 2370 into place, one endof the suture 2375 is pulled and the knot comes free and the suture isremoved, allowing the stent 2372 to open radially and the barbs 2371 toengage the tissue. The barbs 2371 can be located distal to the foam 2374as shown, or pre-engaged with the foam 2374 and penetrating through thefoam 2374.

J. Internal Stent with Increased Embolization Resistance

A metallic stent-like frame 2380 with distal static barbs 2381 and aproximal “speed bump” 2382 is disclosed as shown in FIGS. 70-72. Itcould be a zig-zag stent (as shown) or a wave stent or other similarexpandable embodiment. The bumps 2382 placed on the external portion ofthe metallic stent frame 2380 can be rounded or pointed in design. Theirpurpose is to provide added resistance and stability for the implantwhen deployed in the LAA, to prevent embolization. In the preferredembodiment, the foam “cup” 2384 could be shaped as depicted in FIG. 71to provide added material 2385 on the distal end for an atraumaticbumper when the distal end of the implant is partially deployed from thedelivery catheter. It may or may not have an internal lumen for aguidewire.

K. Constrained Atraumatic Anchor

As shown in FIGS. 73 and 74, a wave or zig-zag or other stent 2390 maybe fabricated with distally located loops 2391 which engage the tissuein the LAA to anchor the implant in place and prevent dislodgementresistance. Because they are round and not sharp, this limits the riskof perforation, however, if a totally rounded loop does not provideadequate dislodgement resistance, the tips can be modified toincorporate a sharp feature. Loop anchors 2391 can be placed on eachstent end or on just a few, so anywhere from 4-16 anchors can be placed.

During delivery of the implant through the vascular system and into theheart and LAA, the loops 2391 are folded toward the center of theconstrained stent and are lined up next to each other, as shown in FIG.75. The inner catheter is placed through the loops 2391 to keep themconstrained. When the system is in the LAA, the outer catheter/sheath isretracted, deploying the proximal portion of the implant. If positioningappears acceptable, the inner catheter can be removed, allowing thedistal portion of the implant to fully expand and the loop anchors toengage the LAA tissue.

L. Perfusion Element & Barb Options

In the event of the implant being dislodged after deployment in the LAA,it is anticipated that the device would travel into the LA, across themitral valve and into the left ventricle, then out the left ventricularoutflow track, across the aortic valve and into the aorta and distalcirculation. In this journey, it is possible that the device may getlodged in any of the above structures, interrupting flow and causingdistal ischemia and possible hemodynamic collapse. It therefore would bedesirable for an implant 2392 to have design features which would allowfor distal perfusion, for example as shown in FIGS. 76 and 77.

FIG. 76 is a top view of an embodiment of the implant showing the leftatrial surface. Within the surface is seen a valve, which in the shownembodiment is a simple cut (A) which would open up when sufficientpressure was applied, allowing for flow through the device 2392. Thisflow could be bi-directional or uni-directional and depending on thespecific conditions allowing for flow rates from 10 ml/min to 5 L/min.In the embodiment as shown, this would be accomplished without loss ofstructural integrity, the loading conditions would result in the device2392 separating into a multiple sub sections each of which would beretrievable using standard technique. A specific device could have asingle valvular element or an array (as shown).

As shown in FIG. 77, in some embodiments, a series of side ports (B) maybe cut in the side wall of the foam 2393 of the implant 2392 to allowfor blood flow in the case of dislodgement and distal embolization.These can vary in size and number from 1-20 ports of about 0.1 mm toabout 5 mm in diameter. They can also vary in shape including but notlimited to circular, oval, and rectangular.

Regarding barb designs, such as those described herein, in addition tohaving an array of barbs deployed at different distances from the LAsurface, barbs can be incorporated which penetrate into the tissue todifferent depths. In one embodiment, the barbs placed most proximal onthe implant can be longer so they penetrate deeper into the thickerproximal LAA tissue whereas those placed most distal on the implant areshorter, so they penetrate less deep into the delicate distal tissue, tomaximize embolization resistance while minimizing the risk ofperforation. In another embodiment the proximal and distal barbs can bethe same length but can be fabricated from different diameters of wireor can be cut at different thicknesses from tubing material, so that thebarbs that engage the more delicate distal LAA tissue are more flexible,or they are designed to primarily engage the internal trabeculationswithin the LAA, whereas the proximally located barbs penetrate thetissue. Alternatively, two barbs can be placed at each crown point ofthe stent, as opposed to one.

M. Multi-Functional Occlusion Devices

FIGS. 78-84 depict various features that may be used, either alone or incombination, with any of the LAA occlusion devices and methods describedherein. In some embodiments, the features of FIGS. 78-84 may beincorporated into the device 3000 and associated features and methodsshown and described with respect to FIGS. 85A-94B.

FIG. 78 is a side view of an embodiment of the LAA occlusion device 3000with ablative features. The LAA occlusion device 3000 has an array ofablative elements 3005. The ablative elements 3005 deliver energy to thetissue in and around the LAA ostium to electrically isolate the LAA. Inthe shown embodiment, the array of ablative elements 3005 is positionedat the proximal end 3004 of the body 3002. The ablative elements 3005may be electrically connected through a deployment catheter to an energysource. Energy may be provided via radiofrequency, ultrasonic,electrical, or other suitable methods. An inner lumen 3003 extendsthrough the body 3002. In some embodiments, there may not be the lumen3003.

FIG. 79 is a side view of an embodiment of the LAA occlusion device 3000with pressure sensing features. The device 3000 has a pressure sensor3007 on its proximal surface 3008. In some embodiments, the sensor 3007may be on the proximal surface 3102 of the proximal cover 3100 (see FIG.85A). In some embodiment, the sensor 3007 does not protrude into theLAA, such as a flat sensor on the proximal surface 3008 or 3102. Thesensor 3007 is electrically connected via a wire 3009 to an electronicelement 3011. The electronic element 3011 has the capability oftransducing and storing the signal generated by the sensor 3007. Thisinformation may be transmitted with a signal 3013 remotely. Theelectronic element 3011 may be powered remotely or by an internalbattery.

FIG. 80 is a side view of an embodiment of the LAA occlusion device 3000with drug elution features. The device 3000 has a sensor 3007 on itsproximal surface 3008. The sensor 3007 may be on the proximal surface3102 of the proximal cover 3100 (see FIG. 85A). The sensor 3007 iselectrically connected via a first wire 3009 to an electronic element3011. The electronic element 3011 is electrically connected via a secondwire 3015 to a drug reservoir 3017 which is fluidly connected via aconduit 3019 to a drug exit port 3021. This allows for drug to bedelivered into the LA, as well as for monitoring concentration ofspecific chemical(s) and or states and to deliver agents in response,e.g., blood sugar level driving insulin delivery. The sensor 3007 maydetect the level of various chemicals and the reservoir 3017 may becontrolled, for example by the electronic element 3011, to elute drugvia the port 3021 in response.

FIG. 81 is a side view of an embodiment of the LAA occlusion device 3000with pacing/defibrillatory features. The device 3000 has an electricalpacing element 3025, such as an electrode. The pacing element 3025extends circumferentially about the body 3002. The pacing element 3025may be in other configurations. The pacing element 3025 is connected bya wire 3027 to a pace generator 3029. The generator 3029 is attached bya wire 3031 to a battery 3033. This pacing system may pace the atriumand defibrillate the atrium when in atrial fibrillation. The generator3029 and/or battery 3033 may include components for controls,communications, commands, etc.

In some embodiments, the LAA may be electrically isolated. The LAA maybe electrically isolated with an occlusion device that incorporates oneor more ablative elements, such as those shown and described withrespect to FIGS. 78-81, conduct the ablation to electrically isolate theLAA, then disengage the occlusion device 3000 leaving it in place withinthe heart. In some embodiments, the LAA may first be electricallyisolated and then the device 3000 implanted, as described herein, forexample with respect to FIGS. 82-84. In some embodiments, conformablecircumferential ablation via a foam plug with ablation elements may beincorporated.

FIGS. 82-84 depict various systems and methods for electricallyisolating the LAA that may be used with the device 3000. In someembodiments, the LAA may be electrically isolated followed by LAAclosure. For example, the systems and methods shown in FIGS. 82-84 maybe used to conduct the isolation, followed by LAA occlusion using thevarious LAA occlusion devices described herein, such as the device 3000.

FIG. 82 is a side view of an embodiment of over the wire circumferentialablation balloon system. An over-the-wire balloon catheter 3035 isplaced over a guidewire 3037 and into the LAA (LAA). The balloon 3039can have one or more circumferential ablative elements 3041, such asapposed radiofrequency (RF) elements, to electrically isolate the LAAusing RF to treat atrial fibrillation. The ablative element 3041 extendscircumferentially about the balloon 3039. The ablative element 3041 maybe in other configurations. This guidewire 3037 may have attached to itsdistal end a balloon 3043 which is inflated in the LAA and serves as abumper to prevent guide catheter 1100 from perforating the wall of theLAA. These features may be similar to those described with respect toFIGS. 8-11.

FIG. 83 is a side view of an embodiment of over the wire circumferentialablation ultrasound balloon system. An over-the-wire balloon catheter3035 is placed over a guidewire 3037 and into the LAA (LAA). A balloon3045, such as a circumferential ablation ultrasound balloon, is used toelectrically isolate the LAA using ultrasound (US) to treat atrialfibrillation. The guidewire 3037 may have attached to its distal end theballoon 3043, as described with respect to FIG. 82.

FIG. 84 is a side view of an embodiment of an over-the-wirecircumferential ablation helical wire system with ablation elements. Anover-the-wire circumferential ablation helical wire 3047 with one ormore ablation elements is placed into the LAA (LAA). The wire 3047 canbe used to electrically isolate the LAA using radiofrequency to treatatrial fibrillation.

N. Embodiments with Compressible Foam Body, Proximal Cover, andCompliant Frame Having Proximal Recapture Struts and Distal Tubular Body

FIGS. 85A-93B show another embodiment of an LAA occlusion device 3000.The device 3000 described herein may have the same or similar featuresand/or functionalities as other LAA occlusion devices described herein,and vice versa. Any of the features of the device 3000 described withrespect to FIGS. 85A-93B may therefore apply to features of the devicesdescribed with respect to FIGS. 1-84, such as the implant 1020, and viceversa.

FIGS. 85A-85C show the LAA occlusion device 3000 having a foam body3002, an expandable support or frame 3040, and a proximal cover 3100.FIGS. 86A-86C show the foam body 3002, with the body 3002 shown incross-section in FIGS. 86B and 86C. FIG. 86C additionally includes thefull view (i.e. non-cross section) of the frame 3040. The device 3000 isshown in an expanded configuration in these figures. The device 3000 hasa longitudinal axis as shown, which may be defined by the foam body3002, as further described.

1. Compressible Foam Body

The body 3002 is formed from a compressible material, such as foam. Thebody 3002 may be a foam formed from reticulated (e.g. net-like)polycarbonate polyurethane-urea. The body 3002 may be cut, formed orassembled into a cup shape, as further described. The body 3002 may havea thickness and compressibility sufficient to engage the surroundingtissue and conform to the anatomic irregularities under radial forceapplied by the inner frame, as further described. The use of acompressible material such as foam for the body 3002 provides a completeseal of the LAA and superior performance for LAA occlusion over existingdevices, as further described. The structure of the foam of the body3002 comprises a three dimensional network of interconnectedreticulations, spaced apart to form a network of interconnected openpores, as further described. The reticulations can carry a coating, suchas PTFE, while preserving the open pores, as further described.

The foam material of the body 3002 has a high porosity. “Porosity” asused herein has its usual and customary meaning and refers to open voidcontent between the interconnected reticulations of the foam. Theporosity of the body 3002 may be at least about 65%, at least about 70%at least about 75%, at least about 80%, at least about 85%, at leastabout 90%, at least about 95% or more. The porosity may be within therange of approximately 90-95%. The porosity may be approximately 90%.The porosity may be approximately 95%. The porosity may be 90%, 91%,92%, 93%, 94%, or 95%. The high porosity promotes quick and tenacioustissue ingrowth, allows it to be compressed into a small catheter,and/or allows blood to pass if the implant embolizes, among otheradvantages.

The foam body 3002 has pores or cells formed between the interconnectedreticulations of the foam material. The foam body 3002 has cells withsizes in the range of from about 250 μm to about 500 μm. The foam mayhave a cell size from about 125 μm to about 750 μm, from about 175 μm toabout 650 μm, from about 200 μm to about 600 μm, from about 225 μm toabout 550 μm, from about 275 μm to about 450 μm, less than 125 μm, orgreater than 750 μm. These sizes may refer to the size of the cell priorto application of any coating, such as PTFE. The cell size may thuschange, e.g. decrease, after application of the coating. The desiredporosity and/or cell size may be determined based on allowing thepassage of blood while blocking debris of a size capable of potentiallycausing ischemic stroke. The allowable size of such debris may drive theselection of the particular porosity and/or cell size. For example, thecell size from about 250 μm to about 500 μm may be based on preventionof debris of a particular size from passing through the body 3002.

In an embodiment, the foam body 3002 is made from a non-resorbable,reticulated, cross-linked, polycarbonate polyurethane-urea matrix,structurally designed to support fibrovascular tissue ingrowth, with afully interconnected, macroporous morphology with over 90-95% voidcontent and cell sizes ranging from 250 to 500 μm.

The body 3002 has a proximal end 3004 and a distal end 3006. In someembodiments, the axial length of the device 3000 from the proximal endto the distal end in a free, unconstrained state is 20 mm. As usedherein, the “free, unconstrained” state, and the like, refers to a stateof the device 3000 without any external forces applied to the device3000 other than a normal or reactive force from a surface (e.g. tabletop) on which the device 3000 is placed. In some embodiments, this axiallength may be from about 10 mm to about 30 mm, from about 12 mm to about28 mm, from about 14 mm to about 26 mm, from about 16 mm to about 24 mm,from about 18 mm to about 22 mm, or about 20 mm. The body 3002 may haveany of these lengths regardless of outer diameter of the body 3002.

The proximal end 3004 of the body 3002 has a proximal end wall or face3008. The proximal face 3008 faces generally toward the LA when thedevice 3000 is implanted into the LAA. The device 3000 may be implantedoff-axis, as further described, in which case the proximal face 3008 maynot reside at a perpendicular to a longitudinal axis of the LA. Theproximal face 3008 thus provides a closed proximal end 3004 of the body3002. The closed proximal end 3004 is configured to span the ostium butthe porosity, as further described, is sufficient to permit the passageof blood while blocking debris of a size capable of potentially causingischemic stroke. This membrane may be formed by the body 3002 and/or thecover 3100. In some embodiments, the proximal face 3008 or portionsthereof may be open. For example, there may not be a proximal face 3008,there may be a partial proximal face 3008, there may be a proximal face3008 with portions removed, etc. In some embodiments, the proximal face3008 or portions thereof is/are not included and any opening or openingsis/are covered by the cover 3100. The size of any such openings in theproximal face 3008 may be driven by the desired size of embolic debristo be prevented from escaping the LAA, as further described.

The proximal face 3008 is flat or generally flat and generallyperpendicular to the longitudinal axis of the device 3000. The proximalface 3008 has a circular or generally circular shape as viewed from theproximal end 3004 in an unconstrained expansion. In some embodiments,the proximal face 3008 may be flat, rounded, segmented, angled withrespect to the longitudinal axis, other shapes, or combinations thereof.The proximal face 3008 may have a non-circular, polygonal, other roundedshape, other shapes, or combinations thereof, as viewed from theproximal end 3004.

The proximal face 3008 has an outer surface 3010 and an opposite innersurface 3012. The outer surface 3010 faces proximally away from thedevice 3000 and the inner surface 3012 faces distally toward the frame3040. The surfaces 3010, 3012 may define outer and inner sides of theproximal face 3008. The thickness of the proximal face 3008 may bemeasured axially between the outer surface 3010 to the inner surface3012. This thickness in a free, unconstrained state (e.g. uncompressedand expanded) may be from about 0.5 mm to about 5 mm, from about 1 mm toabout 4 mm, from about 2 mm to about 3 mm, about 2.5 mm, or 2.5 mm. Insome embodiments, the thickness may be less than 0.5 mm or greater than5 mm. The thickness of the proximal face 3008 may be uniform ornon-uniform. Thus the thickness may be greater or smaller in differentregions of the proximal face 3008.

The body 3002 includes a sidewall 3014 extending distally from theproximal face 3008. The sidewall 3014 extends circumferentially about aperimeter of the proximal face 3008 to form a closed cross-section (i.e.extends circumferentially 360 degrees about the axis). The sidewall 3014extends axially to define a tubular body concentric about thelongitudinal axis of the device 3000. The longitudinal axis extendsthrough a geometric center of the tubular body defined by sidewall 3014.The sidewall 3014 is tubular or generally tubular, e.g. cylindrical,along the axis. In some embodiments, the sidewall 3014 may be conical orfrustoconical, for example where the proximal end is wider than thedistal end or vice versa. The sidewall 3014 may have an outer profile atthe proximal end thereof, and as viewed from the proximal or distal end,to match that of the outer perimeter of the proximal face 3008.

In some embodiments, the cross-section of the sidewall 3014 may not beclosed, for example where there are openings in the sidewall 3014. Thuscross-sections taken at various locations along the longitudinal axismay or may not show a closed section. In some embodiments, the sidewall3014 may be non-tubular, non-cylindrical, non-circular, polygonal, otherrounded shapes, other shapes, or combinations thereof. In someembodiments, as shown, the sidewall 3014 may extend continuously for theentire length from the proximal end 3004 to the distal end 3006. In someembodiments, the sidewall 3014 may not extend continuously for theentire length from the proximal end 3004 to the distal end 3006. Forexample, the sidewall 3014 may include a plurality of disconnectedsections, such as annular portions of the sidewall, located and spacedalong the longitudinal axis and connected to the frame 3040.

The sidewall 3014 has an outer surface 3016 and an opposite innersurface 3018. The outer surface 3016 faces radially outward from theaxis. The inner surface 3018 faces radially inward toward the axis. Thethickness of the sidewall 3014 may be measured radially between theouter surface 3016 to the inner surface 3018. This thickness in a free,unconstrained state (e.g. uncompressed) may be from about 0.5 mm toabout 5 mm, from about 1 mm to about 4 mm, from about 2 mm to about 3mm, about 2.5 mm, or 2.5 mm. In some embodiments, the thickness may beless than 0.5 mm or greater than 5 mm. The thickness of the sidewall3014 may be uniform or non-uniform. Thus the thickness may be greater orsmaller in different regions of the sidewall 3014. The thickness of thesidewall 3014 may be the same or different as the thickness of theproximal face 3008. In some embodiments, the thickness of the proximalface 3008 is 2.5 mm and the thickness of the sidewall 3014 is 2.5 mm. Insome embodiments, the thickness of the proximal face 3008 is about 2.5mm and the thickness of the sidewall 3014 is about 2.5 mm.

The sidewall 3014 has a distal free end 3020 having a distal surface3022. The distal surface 3022 is flat or generally flat andperpendicular to the longitudinal axis of the device 3000. In someembodiments, the distal surface 3022 is non-flat, angled with respect tothe axis of the device 3000, curved, rounded, segmented, other shapes,or combinations thereof.

The body 3002 may have a distal opening 3024. The opening 3024 is formedby the distal free end 3020 of the sidewall 3014. The opening 3024 is ata distal end of an internal central volume or cavity 3028 of the body3002 that is formed at least partially by the sidewall 3014, theproximal face 3008 and/or the shoulder 3030. The frame 3040 may residewithin the cavity 3028, as further described. The distal opening 3024may be completely open. In some embodiments, the distal opening 3024 maybe mostly open, partially open, or closed, for example where the body3002 has a distal face similar to the proximal face 3008 to enclose orpartially enclose the cavity 3028.

The body 3002 has a shoulder 3030, shown as a bevel, that extendsbetween the proximal face 3008 to the sidewall 3014. The shoulder 3030may be an intersection of a proximal end of the sidewall 3014 and theproximal face 3008. The shoulder 3030 extends circumferentially aboutthe entire perimeter of the intersection. The shoulder 3030 has an outersurface 3032. The outer surface 3032 may be a beveled surface. The outersurface 3032 is flat or generally flat in an axial direction. The outersurface 3032 extends circumferentially about the entire perimeter of theshoulder 3030. In some embodiments the shoulder 3030 and/or outersurface 3032 may be non-flat, rounded, other shapes in an axialdirection, or combinations thereof. The shoulder 3030 and/or outersurface 3032 may extend circumferentially less than the entire perimeterof the shoulder 3030. The thickness of the shoulder 3030 may be measuredinward perpendicularly to the outer surface 3032. The thickness of theshoulder 3030 may be the same as the thicknesses of the proximal face3008 and/or the sidewall 3014, as described herein. In some embodiments,the thickness of the shoulder 3030 may be different from the thicknessesof the proximal face 3008 and/or the sidewall 3014. The shoulder 3030may function as a recapture ramp, to facilitate drawing the implantproximally into the deployment catheter.

The compressibility of the body 3002 contributes to the superior sealingcapability of the device 3000. The foam may be compressible to provide alarger radial “footprint” and spread out the radial forces from strutson the frame 3040, as further described. The foam body 3002 may have acompressive strength of at least 1 pound per square inch (psi) or withina range of about 1 psi to about 2 psi, or no more than about 2 psi. The“compressive strength” here refers to the pressure to compress the foamto 50% strain. With some foam materials for the body 3002, the pressuremay not change from 50% strain through at least 80% strain, and therelation of pressure versus strain may be flat or generally flat. Thus,even with thicker foams for the body 3002, the body 3002 will not exertmuch more outward force on the tissue due to the increased thickness byitself. In an embodiment, the foam body 3002 is a reticulated, crosslinked matrix having at least about 90% void content, an average cellsize within the range of from about 250-500 microns, a wall thickness ofat least about 2 mm and a compressive strength of at least about 1 psi.In an embodiment, the body 3002 is formed from a foam material having orsubstantially having the material properties indicated in Table 1. Insome embodiments, the body 3002 is formed from materials described in,for example, U.S. Pat. No. 7,803,395, issued Sep. 28, 2010, and titled“Reticulated elastomeric matrices, their manufacture and use inimplantable devices,” or U.S. Pat. No. 8,337,487, issued Dec. 25, 2012,and titled “Reticulated elastomeric matrices, their manufacture and usein implantable devices,” the entire disclosures of which areincorporated herein by reference.

TABLE 1 Example material properties for an embodiment of foam materialthat may be used for the foam body 3002. Material Property ValuePermeability 311 Darcy Average Cell Size 377 μm Density 2.7 lb/ft³Compressive Strength 1.1 psi Tensile Strength Parallel 68 psi TensileStrength 32 psi Perpendicular Elongation Parallel 219% ElongationPerpendicular 243%

The device 3000 may include markers 3023 (see FIG. 85B; for clarity onlysome of the markers 3023 are labelled in the figures) to facilitatevisualization during delivery. The markers 3023 may be radiopaque markerbands sewn into the distal free end 3020 of the body 3002. The markers3023 may be for visualization using fluoroscopy imaging of the distalend 3006 of the device 3000 during delivery. There may be a series ofthe markers 3023 located circumferentially along the distal surface 3022of the body 3002 (for clarity, only some of the markers 3023 arelabelled in FIG. 85B). In some embodiments, the markers 3023 mayadditionally or alternatively be located in other areas of the body 3002and/or on other parts of the device, such as the cover 3100 or frame3040.

In some embodiments, four platinum iridium (PtIr) radiopaque (RO)tubular markers 3023 are sewn onto the distal end 3006 of the foam body3002 to enable visualization of the distal edge of the device 3000 underfluoroscopy. In some embodiments, a PtIr marker 3023 is attached to thefoam body 3002 at the location of the proximal shoulder 3030 to use as amarker during recapture of the device 3000. Visualization of theproximal and/or distal markers 3023 may facilitate with identifying theamount of recapture. If the device 3000 is recaptured up to but notincluding the anchors proximal 3090 inside the access sheath, the device3000 can be redeployed and reused. If the proximal anchors 3090 arerecaptured into the access sheath, the device 3000 may be removed anddiscarded due to permanent deformation of the anchors 3090. In someembodiments, other materials may be used for the markers 3023, such asgold or other suitable materials.

The foam body 3002 may be attached to various features of the device3000. The body 3002 may be attached to the frame 3040 at numerouspoints, including for example the center of the proximal end of theframe 3040, as further described herein. Attachment can be done usingsuture, such as polypropylene monofilament suture, although othermethods known in the art such as adhesive bonding could be utilized. Theproximal row of proximal anchors 3090 may be individually attached to(e.g. inserted through) the foam body 3002 to prevent relative movementbetween the foam body 3002 and the frame 3040. In other embodiments, thefoam body 3002 could be formed around the endoskeleton so that themetallic frame is within the foam body 3002, eliminating the need for asecondary attachment step. Attachment of the body 3002 to the frame 3040promotes retrieval without damage to the foam body 3002, among otheradvantages. The attachment also ensures that a bumper 3026, furtherdescribed herein, extends beyond the frame 3040 at all times, includingduring initial exposure of the device 3000 upon proximal retraction ofthe delivery sheath.

The foam body 3002 may include a coating. The coating is applied to theinterconnected reticulations of the foam material. The body 3002 may becoated with pure polytetrafluoroethylene (PTFE). The PTFE coatingminimizes the thrombogenicity of the LA surface, while also reducing thefriction of the foam body 3002 against the delivery system to facilitateease of deployment and retrieval. The body 3002 may be coated withconformable, vacuum deposited, pure PTFE. In addition or alternatively,the body 3002 may be coated with a coating other than PTFE. The coating,whether PTFE or otherwise, may be about 0.5 μm thick, and covers atleast a portion of the surface of the interconnected reticulations ofthe foam without occluding the pores. The coating may be applied to someor all of the foam body 3002. The coating may be applied to some or allof the outer surfaces of the foam body 3002.

In some embodiments, the thickness of the coating is from about 0.1 μmto about 1 μm, from about 0.2 μm to about 0.9 μm, from about 0.3 μm toabout 0.8 μm, from about 0.4 μm to about 0.7 μm, about 0.4 μm to about0.6 μm, or about 0.5 μm thick. In some embodiments, greater or smallerthicknesses of the coating may be applied. The coating has a uniform orsubstantially uniform thickness. In some embodiments, the coating mayhave a non-uniform thickness. For example, the portion of the body 3002facing the LA when implanted, such as the proximal face 3008 and/orshoulder 3030, may have a thicker coating relative to a coating alongthe sidewall 3014 of the body 3002. In some embodiments, the outersurface 3010 of the proximal face 3008 has a PTFE coating and theproximal face 3008 also has a ePTFE cover 3100.

The coating is applied using a vapor deposition process. In someembodiments, the coating is applied through coating, vapor deposition,plasma deposition, grafting, other suitable processes, or combinationsthereof. The coating is applied to the outer surfaces 3010, 3032 and3016 of, respectively, the proximal face 3008, the shoulder 3030 and thesidewall 3014. In some embodiments the coating is applied to the outersurfaces 3010, 3032 and only partially on the outer surface 3016. Insome embodiments the coating is applied to outer and inner surfaces ofthe body 3002.

In some embodiments, other biocompatible, thromboresistant and/orlubricious materials could be applied to the surface(s) of the foam body3002 and/or the cover 3100. These materials may encourage tissueingrowth. Such materials may include, for example, heparin, albumin,collage, polyethylene oxide (PEO), hydrogels, hyaluronic acid, materialsthat release nitric oxide, oxygen, nitrogen, amines, bioabsorbablepolymers, and other biomaterials, pharmacologic agents, and surfacemodification materials. Additionally, the surface(s) of the body 3002could be roughened, textured, or otherwise modified or coated to promotehealing or to make it more echogenic.

2. Proximal Cover

The device 3000 may include a cover 3100, which may be an ePTFE cover asfurther described. The cover 3100 is a generally flat material appliedover and covering at least a portion of the body 3002. The cover 3100 ison the proximal end 3004 of the device 3000. The cover 3100 covers theproximal face 3008 of the body 3002 and at least part of the sidewall3014. The cover 3100 covers a proximal portion of the sidewall 3014. Thecover 3100 has a proximal surface 3102 that at least partially faces theLA when implanted. The cover 3100 has an outer edge 3104 forming outervertices 3106 (for clarity, only some of the outer edges 3104 and outervertices 3106 are labelled in the figures). In some embodiments, thecover 3100 may cover only the proximal face 3008 or portions thereof. Insome embodiments, the cover 3100 may extend over more of the sidewall3014, such as the middle or distal portion thereof, or the entiresidewall 3014.

The cover 3100 may have a thickness measured perpendicularly from theproximal surface 3102 to an opposite distal surface of the cover 3100that faces the body 3002. The cover 3100 may have a thickness of 0.001″.In some embodiments, the cover 3100 may have a thickness from about0.00025″ to about 0.005″, from about 0.0003″ to about 0.004″, from about0.0004″ to about 0.003″, from about 0.0006″ to about 0.002″, from about0.0008″ to about 0.0015″, or about 0.001″.

The cover 3100 may be attached to the frame 3040 through the foam body3002. The cover 3100 may in addition or alternatively be attached to thebody 3002. The cover 3100 may be attached at least two or four or six ormore of the outer vertices 3106. The cover 3100 may be attached to theframe 3040 and/or body 3002 at various locations, including at the outervertices 3106, through the proximal surface 3100, at the proximal face3008 of the body 3002, other locations, or combinations thereof. Thecover 3100 is attached using mechanical attachments, such as sutures. Insome embodiments, polypropylene 6-0 sutures are used throughout thedevice to attach the foam body 3002, proximal cover 3100, and RO markers3023 to the foam body 3002 and/or frame 3040. In some embodiments, thecover 3100 is attached to the frame 3040 via standard braided ormonofilament suture material, such as polypropylene, ePTFE, orpolyester. In some embodiments, a polypropylene monofilament isutilized. Proximal anchors 3090 of the frame 3040 (further describedherein) may extend through the outer vertices 3106 of the cover 3100.Such penetrating anchors 3090 may further secure the cover 3100 in placerelative to the body 3002. In some embodiments, the cover 3100 may beattached to the various parts of the device 3000 with mechanicalattachments, fasteners, adhesives, chemical bonds, other suitabletechniques, or combinations thereof.

As shown, the cover 3100 is formed from expanded Polytetrafluoroethylene(“ePTFE”). An ePTFE cover 3100 provides many advantages. For example,the ePTFE cover 3100 may enhance the ability to recapture the device3000 in vivo by distributing the proximal retraction forces applied bythe catheter. The cover 3100 may be an ePTFE material approximately0.001″ thick, with the appropriate porosity to encourage healing andminimize thrombus formation, similar to the underlying PTFE coated foam.

An ePTFE cover 3100 may assist in recapture of the implant into theaccess sheath while providing a smooth, thromboresistant surface whichencourages tissue coverage and integration. The ePTFE may cover theentire proximal face and partially covers the sides, as shown in FIG.85C. The ePTFE cover 3100 is fabricated from a previously laminatedsheet comprised of two or more sheets of oriented material, offset toform a biaxially orientated material. Alternatively, one could use atube, preferably biaxially oriented, that is then cut to form a sheet.The thickness of the final construct can be from 0.0005″-0.005″ but ispreferably about 0.001″.

In some embodiments, the cover 3100 is fabricated from otherthromboresistant, high strength, biocompatible materials, such asknitted or woven polyester fabrics, polypropylene, polyethylene,non-woven vascular scaffolds, porous films, or bioabsorbable scaffoldssuch as polylactic acid, polyglycolic acid, and co-polymers. The shapeof the cover prior to attachment with the device 3000, such as shown inFIG. 88, minimizes wrinkling and provides a smooth surface followingattachment to the implant. This shape may be a star shape, an outerpointed shape, or other shapes.

The cover 3100 may be perforated with a series of openings 3120 (forclarity, only some of the openings 3120 are labelled in the figures).The openings 3120 are perforations or holes formed in the cover 3100 vialaser or mechanical cutting. The openings 3120 include proximal openings3122 and side openings 3124 (for clarity, only some of the proximalopenings 3122 and side openings 3124 are labelled in the figures). Whenthe cover 3100 is assembled with the body 3002, the proximal openings3122 are located over the proximal face 3008 and/or shoulder 3030, andthe side openings 3124 are located over the sidewall 3014. In someembodiments, the cover 3100 includes forty proximal openings 3122. Insome embodiments, the cover 3100 includes forty side openings 3124. Thenumber of openings 3120 located over the proximal face 3008 and/orshoulder 3030 when assembled with the body 3002 may range from ten toeighty, from twenty to seventy, from thirty to sixty, from thirty fiveto fifty, or forty openings 3120. The number of openings 3120 locatedover the sidewall 3014 may range from ten to eighty, from twenty toseventy, from thirty to sixty, from thirty five to fifty, or fortyopenings 3120.

The openings 3120 may have a variety of sizes. The openings 3120 are0.070″ in width, e.g. minor axis, or diameter for circular openings. Theopenings 3120 may have a width from about 0.010″ to about 0.200″, fromabout 0.020″ to about 0.150″, from about 0.030″ to about 0.110″, fromabout 0.040″ to about 0.100″, from about 0.050″ to about 0.090″, fromabout 0.060″ to about 0.080″, or about 0.070″. In some embodiments, thewidth may be less than 0.010″ or greater than 0.200″, such as 0.25″,0.5″ or greater. These widths may apply to circular as well asnon-circular shaped openings 3120.

In some embodiments, the openings 3120 may be various shapes. Theopenings 3120 may be elongated slots. The openings 3120 may extendradially along the cover 3100 from or near a center portion of theproximal surface 3102 toward and/or to the outer edge 3104. The openings3120 may be annular openings extending circumferentially along the cover3100 and having varying radial positions. The openings 3120 may be ofuniform size and shape. Some of the openings 3120 may have varied sizesand/or shapes with respect to other of the openings 3120. The openings3120 may have various distributions or concentrations about the cover3100. For example, the openings 3120 may be more densely located invarious areas, such as along the proximal surface 3102 that faces theLA, along the shoulder 3030, etc.

The openings 3120 enable blood to flow through the device 3000. Theopenings 3120 may allow blood to adequately flow through the device 3000and thereby mitigate the risk of occlusion in the bloodstream should thedevice 3000 embolize within the vasculature system. In some embodiments,should the device 3000 embolize, it may act as a stationary filter atlow pressures but may pass through the bloodstream at higher pressures.In some embodiments, the device 3000 allows for about two to aboutfourteen liters, from about four to about twelve liters, from about sixto about ten liters, or from about eight liters per minute of blood topass at <30 mmHg pressure drop to prevent shock in the event of a deviceembolization. In some embodiments, there are forty circular openings3120 each having a diameter of 0.070″, and allowing for approximatelyeight liters per minute of blood to pass at <30 mmHg pressure drop. Insome embodiments, the proximal end of the device 3000 may be a foamlayer such as the foam proximal face 3008 or a membrane such as thecover 3100 or both, enclosing the cavity 3028 defined within the tubularside wall 3014 of the body 3002. In one implementation, having both thefoam proximal face 3008 and the cover 3100, the foam body 3002 has theopen cell structure further discussed herein that can permit the passageof blood but block escape of embolic debris. The cover 3100 may beocclusive to blood flow, and is present to provide structural integrityand reduced friction for retracting the expanded body 3002 back into thedeployment catheter. In one implementation, the cover 3100 is ePTFE in aform that is substantially occlusive to blood flow, as described. Inthis embodiment, the cover 3100 is therefore provided with a pluralityof perfusion windows or openings 3120, so that blood can pass throughthe open cell foam and cover 3100 but the device 3000 still benefitsfrom the other properties of the cover 3100.

FIGS. 87A-87C depict an embodiment of the LAA occlusion device 3000having another embodiment of a cover 3300. The device 3000 includes thefoam body 3002 and the frame 3040, and features thereof, as describedherein, and additionally includes the cover 3300. The cover 3300 mayhave the same or similar features and/or functionalities as the cover3100, and vice versa. The cover 3300 is on the proximal end 3004 of thedevice 3000. The cover 3300 covers the proximal face 3008 of the body3002 and a proximal part of the sidewall 3014. The cover 3300 has aproximal surface 3302. The cover 3300 has an outer edge 3304 forming aplurality of at least two or four or six or eight or ten or more outervertices 3306 (for clarity, only some of the outer vertices 3306 arelabelled in the figures). The cover 3300 is attached to the body 3002 atthe outer vertices 3306. The proximal anchors 3090 extend through sideopenings 3324 in the outer vertices 3106 of the cover 3100.

The cover 3300 includes a series of openings 3320. The openings 3320include proximal openings 3322, shoulder openings 3323, and the sideopenings 3324. The proximal openings 3322 are located over the proximalend 3004 of the body 3002. The shoulder openings 3323 are located overthe shoulder 3030, e.g. a bevel, of the body 3002. The side openings3324 are located over a proximal portion of the sidewall 3014 of thebody 3002. The proximal anchors 3090 may extend through the sideopenings 3324 that are located in the outer vertices 3106. The openings3320 may have the same or similar features and/or functionalities as theopenings 3120, and vice versa. In some embodiments, the proximal anchors3090 may extend through the cover 3300 material at or near the outervertices 3106.

FIG. 88 shows another embodiment of a cover 3150 that may be used withthe device 3000. The cover 3150 may have the same or similar featuresand/or functionalities as the cover 3100 and/or cover 3300, and viceversa. The cover 3150 may be used to cover the proximal face 3008 of thebody 3002 and part of the sidewall 3014. The cover 3150 has a proximalsurface 3152. The cover 3150 has an outer edge 3154 forming outervertices 3156. The cover 3150 may be attached to the body 3002 at theouter vertices 3156. The proximal anchors 3090 may extend through theouter vertices 3156 of the cover 3100. The cover 3150 includes a seriesof openings 3170. The openings 3170 include proximal openings 3172 andside openings 3174 (for clarity, only some of the openings 3170, 3172,3174 are labelled in the figures). When the cover 3150 is assembled withthe body 3002, the proximal openings 3172 are located over the proximalend 3004 and the side openings 3174 are located over the sidewall 3014.As shown, the openings 3174 may be substantially uniformly located alongthe cover 3150 except for a center region of the proximal surface 3152.

3. Compliant Frame

The expandable and compliant support or frame 3040 is shown in FIGS.85B, 86C and 87C. FIGS. 89A and 89B are side and proximal perspectiveviews, respectively, of the frame 3040 shown in a deployed configurationand in isolation from the rest of the device 3000. The frame 3040provides a compliant structure with anchors to facilitate delivery,anchoring, retrieval and to enable the foam body 3002 to compressagainst the LAA tissue to facilitate sealing, among other things, asfurther described. The frame 3040 is located inside the cavity 3028formed by the foam body 3002. In some embodiments, the frame 3040 may belocated partially or entirely inside one or more portions of the body3002, e.g. within the proximal face 3008 and/or the sidewall 3014, asfurther described. For example, the frame 3040 may be partially locatedwithin the sidewall 3014 as shown in FIG. 87C.

The frame 3040 has a proximal end 3042 and an opposite distal end 3004.The frame 3040 may be tubular, e.g. cylindrical, in a free,unconstrained state. Thus the width of the proximal end 3042 may be thesame or similar to the width of the distal end 3004 in the free,unconstrained state. In some embodiments, the frame 3040 or portionsthereof may be conical or frustoconical, e.g. where in the free,unconstrained state the width of the proximal end 3042 is greater thanthe width of the distal end 3004 or vice versa.

At the proximal end 3042, the frame 3040 has a proximal hub 3050, shownas a cylindrical nipple. The hub 3050 is a rounded, structural endpiece. The hub 3050 may be tubular, e.g. circular and having thecylindrical shape as shown, or may be rounded, non-circular, segmented,other shapes, or combinations thereof. The hub 3050 extends axially andmay have a central lumen. The hub 3050 may be wider than it is long, orvice versa. The hub 3050 is hollow and has a sidewall defining a spacetherethrough, such as a longitudinal opening. In some embodiments, thehub 3050 may be partially hollow, solid, or other configurations. Thehub 3050 facilitates delivery and retrieval of the device 3000, asfurther described. The hub 3050 may provide a central structuralattachment, as further described herein. The hub 3050 may be locatedwithin the cavity 3028 at a proximal end thereof. In some embodiments,the hub 3050 may be located partially or entirely within the foam body3002, e.g. within the proximal face 3008.

A pin 3051 is located within the hub 3050 (shown in FIGS. 89A and 89B).The pin 3051 is an elongated, rounded structural element extendinglaterally across the central lumen. “Lateral” here refers to a directionperpendicular or generally perpendicular to the longitudinal axis. Thepin 3051 has a cylindrical shape. The pin 3051 provides a rounded outersurface configured to provide a smooth engagement surface with a tether,as further described. The pin 3051 provides a high strength connectionwith the frame 3040 to allow for pulling on the device 300 withsufficient force to re-sheath the device 3000. The pin 3051 may beformed from Nitinol. The pin 3051 is secured across the width, e.g.diameter, of the proximal hub 3050. The pin 3050 may be secured at itstwo opposite ends with the sidewall of the hub. The pin 3051 isconfigured to be engaged by a tether 3240, which is wrapped around thepin 3051 in sliding engagement for temporary attachment to a deliverycatheter, as further described. In some embodiments, the pin 3051 isassembled with a cap 3180, as further described herein, for example withrespect to FIGS. 90A-90C.

The frame 3040 at the proximal end 3042 includes a proximal face 3060.The proximal face 3060 may be located within the cavity 3028 at aproximal end thereof. In some embodiments, the proximal face 3060 may belocated partially or entirely within the foam body 3002, e.g. within theproximal face 3008 and/or sidewall 3014. The proximal face 3060 includesa series of recapture or reentry struts 3061. The struts 3061 arelocated at a proximal end of the cavity 3028. In some embodiments, thestruts 3061 or portions thereof may be located partially or entirelywithin the foam body 3002, e.g. within the proximal face 3008 and/orsidewall 3014.

The struts 3061 are elongated structural members. The struts 3061 mayhave rectangular, circular or other shaped cross-sections. In someembodiments, the struts 3061 have a cross-section, e.g. rectangular,with a width that is greater than a thickness such that the struts 3061are stiffer in one direction compared to another direction. This widthmay be in the lateral direction or a direction generally perpendicularto the longitudinal axis of the device 3000 when the device 3000 is inthe expanded configuration, with the thickness perpendicular to thewidth. The struts 3061 may be less stiff in the direction of flexing orbending, for example to facilitate contraction and expansion of thedevice 3000 in the delivery and expanded configurations. The struts 3061may be elongated pins. The struts 3061 may extend from the hub 3050, forexample, and incline radially outwardly in the distal direction from thehub 3050. The struts 3061 may be attached inside, outside, and/or at theend of the sidewall of the hub 3050. The struts 3061 may be separateparts that are then attached to the hub 3050, for example welding,bonding, fastening, other suitable means, or combinations thereof. Insome embodiments, some or all of the struts 3061 and the hub 3050 may bea single, continuous structure formed from the same raw material such asa laser cut hypotube. Some or all of the struts 3061 may be attached,e.g. with sutures as described herein, to the body 3002 and/or the cover3100 at one or more attachment locations.

Each recapture strut 3061 may include an inner curved portion 3062connected to a distal end of the hub 3050, a middle straight portion3064, and/or an outer curved portion 3066 (for clarity, only some of theportions 3062, 3064, 3066 are labelled in the figures). In the deployedconfiguration, the inner curved portion 3062 extends from the hub 3050primarily in a distal direction and then curves to face more outwardlyradially. The middle straight portion 3064 extends from the inner curvedportion 3062 primarily radially but also slightly distally. The outercurved portion 3066 extends from the middle straight portion 3064primarily in the radial direction and then curves toward the distaldirection. The portions may have different shapes in the deliveryconfiguration inside a delivery catheter. In the delivery configuration,the portions may extend primarily distally. The portions may then takethe deployed configuration as described upon deployment from thedelivery catheter. In some embodiments, the struts 3061 may includefewer or more than the portions 3062, 3064, 3066.

The device 3000 may include ten of the proximal recapture struts 3061.Such configuration may accompany a device 300 having a foam body 3002with an outer diameter of 27 mm in the free, unconstrained state. Suchconfiguration may accompany a device 300 having a foam body 3002 with anouter diameter of 35 mm in the free, unconstrained state. In someembodiments, the device 3000 may have from about two to about thirty,from about four to about twenty, from about six to about eighteen, fromabout eight to about sixteen, from about ten to about fourteen, or othernumbers of struts 3061.

In the deployed configuration, each strut 3061 extends radially outwardand distally at an angle to the axis. This angle, measured relative to aportion of the axis that extends distally from the device 3000, may befrom about 60° to about 89.9°, from about 65° to about 88.5°, from about70° to about 85°, from about 72.5° to about 82.5°, from about 75° toabout 80°, or other angular amounts. This angle may be much smaller whenthe device 3000 is in the delivery catheter. The struts 3061 may bend orflex when transitioning between, or when positioned in, the delivery andexpanded configurations. The struts 3061 may bend or flex at the innercurved portion 3062, the middle straight portion 3064, and/or the outercurved portion 3066.

The proximal end 3042 of the frame 3040, such as the proximal face 3060,may therefore have a conical shape in the expanded configuration. Theconical proximal face 3060 may facilitate with recapture of the device3000 back into the delivery catheter. For example, the orientation ofthe struts 3061 inclining distally and radially outward from the hub3050 in the expanded configuration provides an advantageous conicalshape to the proximal face 3008 such that distal advance of the deliverysheath over the device 3000 will bias the struts 3061 inward and causethe device 300 to stow back toward the delivery configuration and sizefor retrieval within the catheter.

The proximal face 3060 foreshortens considerably upon expansion of thedevice 3000 relative to the delivery configuration. “Foreshortening”here refers to the difference in axial length of the proximal face 3060between the reduced delivery configuration and the expandedconfiguration (expanded either freely or as implanted). This length maybe measured axially from the distal or proximal end of the hub 3050 tothe distal ends of the outer curved portions 3066 of the recapturestruts 3061. The proximal face 3060 may foreshorten by 50%, 60%, 70%,80%, 90% or more. The proximal face 3060 has significantly moreforeshortening upon expansion than the tubular body 3080, the latter ofwhich may be referred to as the “working length” or “landing zone.” Thelanding zone is further described with respect to the tubular body 3080herein.

As shown, the struts 3061 are angularly spaced about the axis in evenangular increments. That is, looking at the frame 3040 from the distalor proximal end, the angles between the struts may be equal. In someembodiment, the struts 3061 may not be evenly angularly spaced about theaxis as described. The struts 3061 may or may not be symmetricallydisposed about the axis or about a plane that includes the axis.

The frame 3040 includes a tubular body 3080. The body 3080 provides amechanical base structure for the device 3000, as further described. Thetubular body 3080 is attached to a distal end of the proximal face 3060of the frame 3040. The tubular body 3080 extends to the distal end 3044of the frame 3040. The tubular body 3080 is attached at a proximal endto the outer curved portions 3066 of the recapture struts 3061, asfurther described. The tubular body 3080 may be attached to otherportions of the recapture struts 3061. The tubular body 3080 of theframe 3040 may be attached to the body 3002 and/or the cover 3100, e.g.with sutures as described herein, at one or more attachment locations,as further described. The tubular body 3080 may be located within thecavity 3028. In some embodiments, the tubular body 3080 may be locatedpartially or entirely within the foam body 3002, e.g. within thesidewall 3014.

The tubular body 3080 includes a series of proximal struts 3082 anddistal struts 3086 (for clarity, only some of the struts 3082, 3086 arelabelled in the figures). The proximal struts 3082 and/or distal struts3086 may have rectangular, circular or other shaped cross-sections. Insome embodiments, the proximal struts 3082 and/or distal struts 3086have a cross-section, e.g. rectangular, with a width that is greaterthan a thickness, or vice versa, such that the struts 3061 are stifferin one direction compared to another direction. The struts 3061 may beless stiff in the direction of flexing or bending, for example tofacilitate contraction and expansion of the device 3000 in the deliveryand expanded configurations. Proximal ends of pairs of adjacent proximalstruts 3082 join at proximal apexes 3084. Each proximal strut 3082 isconnected at a respective proximal apex 3084 to a respective outercurved portion 3066 of one of the recapture struts 3061. Each distal endof the proximal struts 3082 connects to a distal end of an adjacentproximal strut 3082 and to proximal ends of two distal struts 3086 at anintermediate vertex 3087. Pairs of adjacent distal struts 3086 extenddistally to join at a respective distal apex 3088. A repeating pattern3089, shown as a diamond shape, may be formed by adjacent pairs ofproximal struts 3082 and adjacent pairs of distal struts 3086. Some orall of the proximal struts 3082 and/or distal struts 3086 may beattached, e.g. with sutures as described herein, to the body 3002 and/orthe cover 3100 at one or more attachment locations. Some or all of theproximal struts 3082 and/or distal struts 3086 may be located within thecavity 3028. In some embodiments, some or all of the proximal struts3082 and/or distal struts 3086 may be located partially or entirelywithin the foam body 3002, e.g. within the sidewall 3014.

There are the same number of proximal apexes 3084 as distal apexes 3088.As shown, there are eleven proximal apexes 3084 and eleven distal apexes3088. The number of proximal and distal apexes 3084, 3088 may each be atleast seven, at least eight, at least nine, at least ten, at leasteleven, at least twelve, at least thirteen, at least fourteen, at leastfifteen, at least sixteen, or fewer or more apexes. In some embodiments,there may not be the same number of proximal apexes 3084 as distalapexes 3088. In some embodiments, there may be more than one row of thepattern, e.g. diamond pattern, formed by the proximal struts 3082 anddistal struts 3086. There may be two, three, four or more rows of thepattern. Some or all of the proximal apexes 3084 and/or distal apexes3088 may be attached, e.g. with sutures as described herein, to the body3002 and/or the cover 3100 at one or more attachment locations.

The body 3080 may be tubular, e.g. cylindrical or generally cylindrical,in the expanded configuration. The tubular body 3080 may be cylindrical,rounded, segmented, polygonal, tube-like, other shapes, or combinationsthereof, all of which are subsumed non-exhaustively under the category“tubular.” The tubular shape is formed by the proximal struts 3082 anddistal struts 3086 in the expanded configuration. The tubular shape mayalso be formed by the outer curve portions 3066 of the recapture struts3061 in the expanded configuration. The tubular shape may also be formedby the foam body 3002 exerting an outward radial force on the frame3040. The frame 3040 may therefore have a proximal conical section and acylindrical working length. In some embodiments, the body 3080 may beconical or frustoconical, for example where the distal end is wider thanthe proximal end or vice versa.

The tubular body 3080 may be referred to as a “landing zone,” asdescribed. This landing zone may refer to the axial length of the body3080, from a distal-most end to a proximal-most end at the transition torecapture struts 3061, in the expanded configuration. The landing zonemay have an axial length as measured from the proximal apex 3084 to thedistal apex 3088. The length of the landing zone may be 10 mm or about10 mm. The landing zone may have a length from about 5 mm to about 15mm, from about 6 mm to about 14 mm, from about 7 mm to about 13 mm, fromabout 8 mm to about 12 mm, from about 9 mm to about 11 mm, or otherlengths. The tubular body 3080 may foreshorten slightly upon expansionof the device 3000 relative to the delivery configuration. The tubularbody 3080 has significantly less foreshortening upon expansion than thelength of the proximal face 3060. The tubular body 3080 may foreshortenby no more than about 5%, 10%, 15%, 20% or 30%.

The frame 3040 self-expands upon delivery from the sheath. The proximalface 3060 and the tubular body 3080 will self-expand. Upon expansion,the radially outward portions of the tubular body 3080 will contact andcompress the foam body 3002 against tissue of the LAA wall. The tubularbody 3080, for example the proximal struts 3082 and distal struts 3086,will contact the inner surface 3018 of the sidewall 3014 and pressagainst the sidewall 3014 so that the outer surface 3016 of the sidewall3014 contacts and compresses against the LAA wall.

When compressed against the LAA wall, the foam body 3002 provides alarger “footprint” than the skeletal frame 3040 components and forms acomplete seal. Thus, the sidewall 3014 acts as a force dissipationlayer, spreading radial force out from the struts 3082, 3086 of theframe 3040 over a larger area than just the area of the individualstruts 3082, 3086 (e.g. a larger area than just the area of the radiallyouter surfaces of the struts 3082, 3086). The use of the foam materialin the body 3002 and the thickness of that foam, such as 2.5 mm, provideadvantages in this regard over devices with thinner and less resilientmaterials than foam. For example, thin fabrics or similar materials thatare pressed against the LAA wall with a skeletal frame will not spreadthe radial force out, and may even sag or otherwise bend, creating gapsand an unsealed portion of the LAA wall. The foam body 3002 as describedherein will take the shape of the LAA wall to create a completecircumferential seal and will also spread out the radial forces from theframe 3040 to create a stronger seal and retention with the foam body3002.

Further, the device 3000 described herein with the compressible body3002 allows for a structural frame 3040 that is compliant due to thesmaller required radial force from the frame 3040. For example, existingdevices with a non-compressible fabric material will have a lesseffective seal, and so the structural elements of those devices mustprovide larger radial forces to compensate and ensure an effective seal,resulting in a less compliant device. In contrast, the current device3000 provides advantages in this regard by having the compressible foambody 3002, allowing for among other things smaller radial forces from,and thus better compliance of, the frame 3040, while still providing aneffective seal. This structural configuration has a cascading effect interms of performance advantages. For instance, the compliance of thedevice 300 allows for delivery off-axis while still providing aneffective seal, among other advantages as further described herein.

The frame 3040 includes a series of proximal anchors 3090. Each proximalanchor 3090 extends from a respective intermediate vertex 3087. Theproximal anchors 3090 may extend from other portions of the tubular body3080. As shown, in the deployed configuration, the proximal anchors 3090extend from the tubular body 3080 radially and proximally. The proximalanchors 3090 may extend into an adjacent region of the sidewall 3014.The proximal anchors 3090 may extend through the outer surface 3016 ofthe sidewall 3014 to penetrate tissue adjacent the device 3000.

The frame 3040 includes a series of distal anchors 3094. Each distalanchor 3094 extends from a respective distal apex 3088. The distalanchors 3094 may extend from other portions of the tubular body 3080. Asshown, in the deployed configuration, the distal anchors 3094 extendfrom the tubular body 3080 radially and proximally. The distal anchors3094 may extend into an adjacent region of the sidewall 3014. The distalanchors 3094 may extend through the outer surface 3016 of the sidewall3014 to penetrate tissue adjacent the device 3000. The anchors 3090,3094 may incline radially outward in a proximal direction to engage thetissue to resist proximal movement of the device 3000.

The anchors 3090, 3094 are elongated structural members. The tips of theanchors 3090, 3094 may be sharpened to facilitate tissue engagement andpenetration. The anchors 3090, 3094 may be straight, extending generallyalong a local axis thereof. The anchors 3090, 3094 may have a curved orother non-straight proximal portion where they attach to the tubularbody 3080. In some embodiments, the anchors 3090, 3094 or portionsthereof may be non-straight, curved, rounded, segmented, othertrajectories, or combinations thereof. In some embodiments, the tissueengaging tips may be curved. In some embodiments, the anchors 3090, 3094may have engagement features extending radially away from the anchor3090, 3094, such as barbs, hooks, or other features.

The cross-section of the anchors 3090, 3094 may be rectangular. In someembodiments, the cross-section may be circular, rounded, non-rounded,square, rectangular, polygonal, other shapes, or combinations thereof.The cross-sections may or may not be uniform along the length of theanchor 3090, 3094. The anchors 3090, 3094 may be about 0.006″ thick andabout 0.008″ wide. The anchors 3090, 3094 may range from about 0.003″ toabout 0.009″ in thickness and from about 0.003″ to about 0.015″ inwidth. The cross-section of the anchors 3090, 3094 may reduce in size,for example taper, toward the distal tip.

In some embodiments, the anchors 3090, 3094 in the deployedconfiguration are inclined at an incline angle of about 30° relative toa portion of the central axis that extends proximally from the device3000. This incline angle may be from about 10 degrees to about 50°, fromabout 15° to about 45°, from about 20° to about 40°, from about 25° toabout 35°, or about 30°. This incline angle of the anchors 3090, 3094 inthe delivery configuration may be smaller than in the deployedconfiguration.

The anchors 3090, 3094 may have various lengths. The length of theanchor 3090, 3094 is measured from a proximal end that connects to thetubular body 3080 to a distal tissue engaging tip of the anchor. In someembodiments, the length of the anchors 3090, 3094 may be from about 0.5mm to about 10 mm, from about 1 mm to about 9 mm, from about 2 mm toabout 8 mm, from about 3 mm to about 7 mm, from about 4 mm to about 6mm, about 5 mm, or other greater or lesser lengths. In some embodiments,the anchors 3090, 3094 are 5 mm long. In some embodiments, the anchors3090, 3094 are about 5 mm long. In some embodiments, the anchors 3090,3094 have a length of at least 2.5 mm, at least 3 mm, at least 3.5 mm,at least 4 mm, at least 4.5 mm, at least 5 mm or more. The anchors 3090,3094 may each be the same or similar length. In some embodiments, theanchors 3090, 3094 may not be the same length. In some embodiments, someor all of the proximal anchors 3090 may have lengths that are less thanor greater than some or all of the lengths of the distal anchors 3094.

In the expanded configuration, the anchors 3090, 3094 extend for alength outside of the uncompressed sidewall 3014. This length of theanchor 3090, 3094 is measured along a local longitudinal axis of theanchor from the outer surface 3016 of the body 3002 to the distal tip ofthe anchor. The anchors 3090, 3094 may extend through the sidewall 3014and/or the cover 3100, and then be trimmed so that the anchors 3090,3094 extend beyond the sidewall 3014 and/or cover 3100 by the desiredlength. In a free, unconstrained state, the anchors 3090, 3094 extendabout 0.5 mm beyond the outer surface 3016 of the sidewall 3014. In someembodiments, in the free, unconstrained state, the anchors 3090, 3094extend beyond the outer surface 3016 of the sidewall 3014 for a lengthof from about 0.1 mm to about 1.5 mm, from about 0.2 mm to about 1.25mm, from about 0.3 mm to about 1.0 mm, from about 0.4 mm to about 0.8mm, from about 5 mm to about 0.6 mm, or other greater or lesser lengths.In a compressed state, such as in the delivery configuration or afterimplantation, the anchors 3090, 3094 extend about 1.0 mm beyond theouter surface 3016 of the sidewall 3014. In some embodiments, in thecompressed state, the anchors 3090, 3094 extend beyond the outer surface3016 of the sidewall 3014 for a length of from about 0.25 mm to about2.5 mm, from about 0.5 mm to about 2 mm, from about 0.75 mm to about 1.5mm, from about 0.875 mm to 1.125 mm, or other greater or lesser lengths.

The geometry of the anchors 3090, 3094 provides several advantages. Forexample, the relatively long length allows for flexibility of theanchors 3090, 3094. This provides for potentially less trauma to the LAAtissue should the device 3000 need to be unanchored and/or retrieved.The anchors 3090, 3094 are less susceptible to loss of strength withoff-axis orientation within the LAA. Further, the anchors 3090, 3094provide high resistance to pull out. For instance, the device 3000 mayprovide at least about 0.5 lb-force of dislodgment resistance from theLAA. Such pullout tests may be simulated with in vitro or benchtopmodels, as further described below.

The anchors 3090, 3094 in the illustrated embodiment are located in twocircumferential rows. One row is located proximal to the other distalrow. Each row has ten anchors each. This configuration may beincorporated, for example, in the device 3000 having a foam body 3002with a free, unconstrained outer diameter of 27 mm. Each row may havefourteen anchors each. This configuration may be incorporated, forexample, in the device 3000 having a foam body 3002 with a free,unconstrained outer diameter of 35 mm. In some embodiments, a single rowof anchors 3090, 3094 may have from two to twenty-four, from four totwenty-two, from five to twenty, from six to eighteen, from seven tosixteen, from eight to fifteen, from nine to fourteen, from ten tothirteen anchors, or greater or fewer amounts of anchors 3090 or 3094.In some embodiments, there may only be one row or greater than two rowsof anchors. The anchors 3090, 3094 may be spaced circumferentially in asingle row.

In embodiments with multiple rows of anchors 3090, 3094, the rows may becircumferentially offset, as shown. That is, as viewed from the proximalor distal end of the device 3000, the anchors 3090, 3094 are angularlyspaced apart from each other about the axis. The anchors 3090, 3094 maynot be circumferentially offset, e.g. they may be evenly angularlyspaced when viewed as described. The anchors 3090, 3094 are locatedaxially at or near a middle portion of the sidewall 3014. The anchors3090, 3094 may be located such that the tips of the anchors 3090, 3094extend to adjacent tissue at a middle portion of the sidewall 3014. Theoffset and middle locations of the anchors 3090, 3094 may ensureengagement with the LAA tissue distal to the ostium. Having the anchors3090, 3094 located at the largest width, increases the stability of thedevice 3000. With a generally cylindrical shaped device 3000, theanchors 3090, 3094 effectively sit on the largest diameter of the device3000. In some embodiments, the anchors 3090, 3094 may be locatedproximal, distal, or centrally along the length of the frame body 3080.In some embodiments, the anchors 3090, 3094 may not be offset and/or maynot be angularly evenly spaced.

The anchors 3090, 3094 may provide advantageous flexibility, asdemonstrated by pullout tests and in comparison to existing devices. Forexample, the device 3000 was tested to determine the force required todislodge the device 3000 from a simulated tissue model by pulling thedevice 3000 proximally outward from the model. A low durometer siliconetube with a circular inner diameter (ID) was used as the model. For thedevice 3000 having a foam body 3002 with a 27 mm outer diameter in afree unconstrained state, tubes with ID's of 16.5 mm, 21 mm and 25 mmwere tested. The pullout forces for existing devices drop offsignificantly going up to a 21 mm model, whereas the forces for thedevice 3000 drop only slightly.

In the largest diameter (25 mm) model, where there is not a lot ofinterference in the fit, the forces for the existing devices approachzero as the device does not engage the model wall because the anchorsare sitting at a smaller diameter on a trailing edge of the device. Thedevice 3000 consistently resists dislodgment with about 0.7 lbs offorce. Since there is very little friction resisting pullout, that forceis almost entirely resisted by the anchors 3090, 3094. When examiningfailure modes, all devices eventually begin to slide out of the model.Upon failure, the anchors 3090, 3094 fold backward or sideways beforeslipping starts. Assuming 0.7 lbs force is required to cause all twentyanchors 3090, 3094 to fold backward, then the force per anchors isestimated to be about 0.035 lbs.

The frame 3040 may be laser cut. The tubular body 3080 may be laser cutfrom a single tube. The body 3080 may be cut from a tube having athickness from about 0.002″ to about 0.014″, or about 0.008″. The tubemay have an outer diameter (OD) from about 0.05″ to about 0.30″. Thetube may have an outer diameter (OD) of 0.124″ for the 27 mm device 3000(i.e. the embodiment of the device 3000 having a foam body 3002 with anOD of 27 mm in the unconstrained, free state). The tube may have an ODof 0.163″ for the 35 mm device 3000 (i.e. the embodiment of the device3000 having a foam body 3002 with an OD of 35 mm in the unconstrained,free state).

In some embodiments, the body 3080 is laser cut from a superelasticnitinol tube, however, numerous other biocompatible metallic materialscan be utilized such as shape memory Nitinol, stainless steel, MP35N, orElgiloy. The frame 3040 is self-expandable. In some embodiments, aballoon-expandable frame 3040 could be utilized. Additionally, the body3080 could be fabricated from drawn wire as opposed to being laser cutfrom a tube.

As shown, an embodiment of the device 3000 includes the frame 3040having ten proximal recapture struts 3061 and twenty total anchors 3090,3094, with the foam body 3002 having an outer diameter of 27 mm. In someembodiments, the device 3000 may include the frame 3040 having fourteenproximal recapture struts 3061 and twenty-eight total anchors 3090,3094, with the foam body 3002 having an outer diameter of 35 mm.

In one embodiment, the frame 3040 includes a proximal hub 3050, tetherpin 3051, front face with ten or fourteen recapture struts 3061, adiamond pattern cylindrical body 3080, and twenty or twenty-eightanchors 3090, 3094. The frame proximal face 3060 supports recapture, theframe body 3080 supports the foam cylinder body 3002, and the anchors3090, 3094 located on the cylinder provide resistance to embolization.

The design of the device 3000 provides numerous advantages, some ofwhich have been described. As further example, the frame 3040 providesmany advantages, including but not limited to: 1) implant radialstiffness/compliance—the frame 3040 provides enhanced radial stiffnesswhile still being sufficiently compliant to allow for off-axisimplantation, recapture, etc.; 2) dislodgement resistance—the frame 3040provides for high pullout strength, as described; 3) transcatheterdelivery—the frame 3040 can be compressed into a delivery catheter andthen fully expand when delivered; 4) recapture—the frame 3040 allows forrecapture/retreival into the delivery catheter after deployment or evenafter implantation in the LAA; and 5) mechanical integrity—the frame3040 has acute and long term structural integrity, for example theability to withstand loading into the delivery catheter, deployment fromthe catheter, and cyclic loading/fatigue. The frame 3040 also provides aconformable structure to enable the foam body 3002 to compress againstthe LAA tissue to facilitate sealing and anchoring with minimalcompression (oversizing). The resulting compliance of the frame 3040provides better anchoring than existing solutions, as described.

As further example, the device 3000 seals against irregularly shaped LAAostia and necks. For instance, a combination of a Nitinol frame 3040with a foam body 3002 having a coating of PTFE and cover 3100 of ePTFEcontribute to ability of the device 3000 to conform to the anatomy andseal against irregular projections and shapes, while providing a smooththromboresistent LA surface.

As further example, the device 3000 provides for controlled & safedelivery. The design of the combined frame 3040 and foam body 3002facilitates delivery in a controlled fashion by slowing the speed ofexpansion. The bumper 3026 acts as an atraumatic leading edge portionwhen delivering the implant into the LAA mitigating the risk of injury.The user has the ability to recapture and redeploy the device 3000, ifnecessary. A flexible tether 3240 attachment, as further described, fromthe delivery catheter to the device 3000 permits the device 3000 to sittension free immediately following implantation so the user can ensurefinal appropriate positioning prior to release of the device 3000.

As further example, the device 3000 provides for simplified placement.The foam-covered cylindrical design makes alignment of the device 3000with the central axis of the LAA during delivery non-critical (byallowing deployment up to, for example, 45 degrees off-axis), which isdesigned to simplify the implantation procedure, as further described.

As further example, the device 3000 provides for simple sizing. The foamand frame design contributes to the ability to need only two diameters(e.g., 27 mm and 35 mm) to seal the range of expected LAA configurationsand diameters (e.g. targeting LAA diameters of 16 to 33 mm). Theconformability of the foam and frame allow the 20 mm long implant to fitinto LAA's as short as 10 mm deep. The short landing zone requirement(LAA depth) of the device 3000, combined with the need for only twoimplant diameters, enables treatment of a wide range of LAA anatomieswith minimal need for burdensome echo and CT sizing. The conformingnature of the implant is key to facilitating a simple to use productplatform that is adaptable to a variety of anatomic structures.

As further example, the device 3000 provides thromboresistant materialsand design. The removable tether leaves a smooth, metal-free surface inthe LA. Thromboresistant materials (PTFE-coated foam and an ePTFE cover)create a smooth LA face (no metal attachment connection) to reduceanticoagulation needs, enhance thromboresistance, and encourageendothelialization.

As further example, the device 3000 provides thin, low profile anchors3090, 3094 around the midpoint of the device 3000 to provide secure yetatraumatic anchoring.

4. Distal Bumper

The foam body 3002 has a distal bumper 3026. The bumper 3026 may be afoam distal region of the body 3002, such as a distal portion of thesidewall 3014. The bumper 3026 may be a portion of the foam body 3002that extends beyond the distal end 3044 of the frame 3040. The bumper3026 may extend beyond the distal end 3044 of the frame 3040 in thedelivery configuration and in the deployed configuration. The body 3002may be attached to the frame 3040 in various locations such that thebody 3002 may stretch in some embodiments, for example in the deliveryconfiguration, to ensure the bumper 3026 extends beyond the frame 3040upon initially retracting the sheath during delivery.

The device 3000 can conform both in length and diameter due toconformability of both the foam body 3002 and the frame 3040. Thisallows for the device 3000 to accommodate most patient LAA anatomieswith only a couple or few different sizes of the device 3000, such as 27mm and 35 mm outer diameter body 3002 as described herein, and onelength, such as 20 mm. The frame 3040 may thus be shorter than the foambody 3002, resulting in some embodiments in about 5 mm of foam bumper3026 distal to the distal-most end of the frame 3040. The distal bumper3026 acts as an atraumatic tip during delivery of the device 3000 andcan be compressed following implantation to allow the device 3000 toconform to appendages with a depth (landing zone) as short as 10 mm.This ability to conform both in length and diameter is due to theconformability of both the foam body 3002 and the frame 3040.

The length of the bumper 3026 may be measured axially from thedistal-most end of the frame 3040 to the distal surface 3022 of the body3002. For example, the bumper 3026 may extend from the distal apexes3088 to the distal surface 3022. The bumper 3026 may have a length of 5mm or about 5 mm. The bumper 3026 may have a length of about 1 mm, 2 mm,3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm or more. The bumper 3026 mayhave a length from about 2.5 mm to about 7.5 mm, from about 3 mm toabout 7 mm, from about 3.5 mm to about 6.5 mm, from about 4 mm to about6 mm, from about 4.5 mm to about 5.5 mm.

5. Cap & Pin

FIGS. 90A-90C are proximal perspective views of the frame 3040 having acap 3180. FIG. 90D is a distal perspective view of the cap 3180. In someembodiments, the pin 3051 is placed across the proximal hub 3050diameter and serves to engage the delivery catheter tether 3240 (e.g. asuture), which is wrapped around the pin 3051 for temporary attachmentto the delivery catheter 3220, as described further herein for examplewith respect to FIGS. 89A-89B. As shown, the hub 3050 has a pair ofopposite side openings 3053 extending through a sidewall of the hub3050. The cap 3180 has a corresponding pair of opposite side openings3190 extending through a sidewall 3184 of the cap 3180. When the cap3180 is assembled with the hub 3050, the pin 3051 may be insertedthrough the aligned pairs of openings 3053, 3182. The assembly can befurther secured by welding the ends of the pin 3051 to the hub 3050.

As shown in FIG. 90D, the cap 3180 includes a proximal end 3182 and adistal end 3184. The cap 3180 includes a rounded sidewall 3186 extendingfrom the proximal end 3182 to the distal end 3184. The sidewall 3186defines a longitudinal opening 3188 through the cap 3180. The sidewall3186 includes a pair of lateral openings 3190 located opposite eachother. The cap 3180 includes a flange 3192 at the proximal end 3182extending radially outward.

The cap 3180 is formed from titanium and the pin 3051 is formed fromNitinol or superelastic Nitinol. In some embodiments, the cap 3180and/or pin 3051 may be formed from other materials, for example numerousbiocompatible metallic or polymeric materials such as shape memoryNitinol, stainless steel, MP35N, Elgiloy, polycarbonate, polysulfone,polyether ether keytone (PEEK), or polymethyl methylacrylate (PMMA) orother materials.

The cap 3180 and pin 3051 facilitate attachment to the tether 3240. Thecap 3180 and pin 3051 also mitigate damage to the foam body 3002 duringrecapture of the device 3000. The cap 3180 also creates an atraumaticsurface for the hub 3050 of the frame 3040. For example, the cap 3180may prevent the hub 3050 from cutting through the foam body 3002 as thedevice 3000 is collapsed into an access sheath. Without the cap 3180,the sharp edges of the hub 3050 may shear through the foam body 3002during recapture of the device 3000 into the access sheath.

6. Loading System

FIG. 91 is a side view of an embodiment of a loading system 3200 forloading the device 3000 into a delivery catheter 3220. The system 3200includes a loading tool 3210. The loading tool 3210 has a conicalportion 3212, having a distal opening 3213, and a cylindrical portion3214. The delivery catheter 3220 extends through the cylindrical portion3214 with a distal end 3222 of the delivery catheter 3220 located withinthe cylindrical portion 3214. A pusher 3230 extends through the deliverycatheter 3220. A tether 3240 (see FIG. 92) is attached to the device3000 and extends through the loading tool 3210, the delivery catheter3220 and the pusher 3230. The tether 3240 and pusher 3230 are pulled inthe proximal direction while the delivery catheter 3230 and the loadingtool 3210 are held stationary. The device 3000 is compressed laterallyby the conical portion 3212 as the device 3000 is pulled proximally bythe tether 3240 through the loading tool 3210. A distal end 3232 of thepusher 3230 remains adjacent to the proximal end 3004 of the device 3000as the device 3000 is loaded into the delivery catheter 3220. Theremovable tether 3240, which may be fabricated from ultra-high molecularweight polyethylene (UHMWPE), is used to attach the implant to thedelivery catheter.

In some embodiments, the conical portion 3212 of the loading tool 3210has a chamfered distal edge of approximately 45°-75° (degrees),preferably 60°. In some embodiments, the conical portion 3212 has adistal inner diameter (ID) greater than the outer diameter (OD) of thedevice 3000 and an angle of ideally between 15° and 25°, and in oneimplementation about 20°, to appropriately collapse the anchors 3090,3094 which may protrude off the foam body 3002 surface at an angle of30° or about 30°. The gradual taper of the loading tool 3210 ensures,for example, that the frame 3040 folds evenly without crossovers orextra strain.

7. Delivery System

FIG. 92 is a side view of a schematic of a delivery system 3201 fordelivering the device 3000. The delivery system 3000 includes thedelivery catheter 3220 having a distal end 3222 and a proximal end 3224.The delivery system 3000 includes the pusher 3230 having the distal end3232 and a proximal end 3234. The tether 3240 includes a first end 3242and a second end 3244. A restraint 3246 secures the first and secondends 3242, 3244.

To deliver the device 3000 to the LAA, an access sheath is placed acrossthe interatrial septum into the LAA through which the delivery catheter3220, containing the device 3000, is placed. The device 3000 is loadedinto the distal end 3222 of the delivery catheter 3220 using the loadingtool 3210, either at the point of manufacture or at the treatment site.To load the implant, the pusher and tether are pulled proximally,collapsing the implant as it enters the tip of the delivery catheter.Once the loaded delivery catheter is placed through the sheath into theLAA, the pusher rod is held steady as the delivery catheter and accesssheath are simultaneously retracted proximally, deploying the implant

The tether 3220 passes from the proximal end of the delivery catheter3220, through the catheter pusher 3230, around the implant tether pin3051, and back through the delivery catheter 3220. When both ends of thetether 3230 (held together by the restraint 3246 at the proximal end ofthe catheter) are pulled, the device 3000 is pulled into the deliverycatheter 3220. Once the device 3000 is properly placed in the anatomy,one end of the tether 3240 is cut and the entire tether 3240 can beremoved from the system, disengaging from the pin 3051.

8. Tether Release System

FIGS. 93A and 93B are proximal and distal perspective views respectivelyof a tether release system 3400. The release system 3400 includes a tube3420 and a lock 3402. The tube 3420 has a proximal end 3422 and a distalend 3424. An opening 3426 extends through the tube 3420.

The lock 3402 includes a proximal end 3404 and a distal end 3406. Anopening 3408 defined by a sidewall 3409 extends through the lock 3402from the proximal end 3404 to the distal end 3406. The tube 3420 extendsthrough the opening 3408 at the proximal end 3404 of the lock 3402 andto the distal end 3406 of the opening 3408. The sidewall 3409 of thelock 3402 has a first groove 3410 extending longitudinally from theproximal end 3404 to the distal end 3406 and extending radiallypartially through the thickness of the sidewall 3409. The sidewall 3409of the lock 3402 has a second groove 3412 extending longitudinally fromthe proximal end 3404 partially along the sidewall 3409 toward thedistal end 3406 and radially partially through the thickness of thesidewall 3409.

The tether 3240 includes a first end 3243 and the second end 3245. Thetether 3240 extends distally from the first end 3243 within the opening3426 of the tube 3240 and out through the distal end 3424 of the tube3420 to the cap 3180. The tether 3240 extends distally into the opening3188 of the cap 3180 and around the pin 3051 and back in the proximaldirection. The tether 3240 then extends proximally into the first groove3410 of the lock 3402, around the proximal end 3404 of the lock 3402,and then distally into and through the second groove 3412. The tether3240 terminates at the second end 3245 in a knot 3247.

In use, the knot 3247 may be secured due to the relative location of thetube 4320 and the pusher 3230 inside the delivery catheter 3230. Theknot 3247 may be prevented from advancing distally due to the innerdiameter of the distal end of the delivery catheter 3230 fitting tightlyabout the outer diameter of the lock 3402. The pusher 3420 may beadvanced distally to expose the second groove 3412 and free the knot3247 from restraint. When the proximal end of the tether 3240 is pulledproximally, the knot 3247 slides distally through the second groove3412, advances around the proximal end 3404 of the lock 3402, advancesdistally through the first groove 3410, into the cap 3180 and around thepin 3051, and then distally through the opening 3408 of the lock 3402and can be retrieved with the pusher 3230.

9. Off-Axis Delivery and Deployment

The device 3000 may be deployed off-axis within an LAA while stillproviding a complete, stable, and atraumatic seal. In some embodiments,the device 3000 may be deployed at an angle of at least about 15° or 25°and in some embodiments as much as 35° or 45°, for example, relative toa central longitudinal LAA axis and still provide an effective seal. TheLAA axis here is defined as the geometric center of the ostium to theLAA, and tracks the best fit geometric center of the LAA cavity.

This ability of the device 3000 to be deployed off-axis is due in partto the relatively thick, compressible foam body 3002 material, thecompliant frame 3040 and the cylindrical shape of the device 3000 withthe foam bumper 3026. The device 3000 is stable within the LAA despitehaving a length that is less than the diameter, or having L/D<1. Asdescribed, the length may be 20 mm for the device 3000 having an OD ofboth 27 mm and 35 mm. Thus not only is flexibility and simplicityallowed with manufacturing processes by having one length, but alsostability and effectiveness of the device in use. Further, the axialcompressibility of the bumper 3026, combined with the axially compliantframe 3040, allows a 20 mm long device 3000 to be placed within a 10 mmdeep LAA, whereas existing LAA closure devices require longer landingzones, or at least landing zones equal to the size of the length of themetallic frame.

Various modifications to the implementations described in thisdisclosure will be readily apparent to those skilled in the art, and thegeneric principles defined herein can be applied to otherimplementations without departing from the spirit or scope of thisdisclosure. Thus, the disclosure is not intended to be limited to theimplementations shown herein, but is to be accorded the widest scopeconsistent with the claims, the principles and the novel featuresdisclosed herein. The word “example” is used exclusively herein to mean“serving as an example, instance, or illustration.” Any implementationdescribed herein as “example” is not necessarily to be construed aspreferred or advantageous over other implementations, unless otherwisestated.

Certain features that are described in this specification in the contextof separate implementations also can be implemented in combination in asingle implementation. Conversely, various features that are describedin the context of a single implementation also can be implemented inmultiple implementations separately or in any suitable sub-combination.Moreover, although features can be described above as acting in certaincombinations and even initially claimed as such, one or more featuresfrom a claimed combination can in some cases be excised from thecombination, and the claimed combination can be directed to asub-combination or variation of a sub-combination.

Similarly, while operations are depicted in the drawings in a particularorder, this should not be understood as requiring that such operationsbe performed in the particular order shown or in sequential order, orthat all illustrated operations be performed, to achieve desirableresults. Additionally, other implementations are within the scope of thefollowing claims. In some cases, the actions recited in the claims canbe performed in a different order and still achieve desirable results.

It will be understood by those within the art that, in general, termsused herein are generally intended as “open” terms (e.g., the term“including” should be interpreted as “including but not limited to,” theterm “having” should be interpreted as “having at least,” the term“includes” should be interpreted as “includes but is not limited to,”etc.). It will be further understood by those within the art that if aspecific number of an introduced claim recitation is intended, such anintent will be explicitly recited in the claim, and in the absence ofsuch recitation no such intent is present. For example, as an aid tounderstanding, the following appended claims may contain usage of theintroductory phrases “at least one” and “one or more” to introduce claimrecitations. However, the use of such phrases should not be construed toimply that the introduction of a claim recitation by the indefinitearticles “a” or “an” limits any particular claim containing suchintroduced claim recitation to embodiments containing only one suchrecitation, even when the same claim includes the introductory phrases“one or more” or “at least one” and indefinite articles such as “a” or“an” (e.g., “a” and/or “an” should typically be interpreted to mean “atleast one” or “one or more”); the same holds true for the use ofdefinite articles used to introduce claim recitations. In addition, evenif a specific number of an introduced claim recitation is explicitlyrecited, those skilled in the art will recognize that such recitationshould typically be interpreted to mean at least the recited number(e.g., the bare recitation of “two recitations,” without othermodifiers, typically means at least two recitations, or two or morerecitations). Furthermore, in those instances where a conventionanalogous to “at least one of A, B, and C, etc.” is used, in generalsuch a construction is intended in the sense one having skill in the artwould understand the convention (e.g., “a system having at least one ofA, B, and C” would include but not be limited to systems that have Aalone, B alone, C alone, A and B together, A and C together, B and Ctogether, and/or A, B, and C together, etc.). In those instances where aconvention analogous to “at least one of A, B, or C, etc.” is used, ingeneral such a construction is intended in the sense one having skill inthe art would understand the convention (e.g., “a system having at leastone of A, B, or C” would include but not be limited to systems that haveA alone, B alone, C alone, A and B together, A and C together, B and Ctogether, and/or A, B, and C together, etc.). It will be furtherunderstood by those within the art that virtually any disjunctive wordand/or phrase presenting two or more alternative terms, whether in thedescription, claims, or drawings, should be understood to contemplatethe possibilities of including one of the terms, either of the terms, orboth terms. For example, the phrase “A or B” will be understood toinclude the possibilities of “A” or “B” or “A and B.”

What is claimed is:
 1. A left atrial appendage occlusion device,comprising: a conformable, tubular foam body, having a closed proximalend and a distal end; the body including a compressible side wallextending between the proximal end and the distal end, and defining acentral cavity; an expandable support coupled with the body, configuredto compress the side wall against a wall of a left atrial appendage; andanchors having tips configured to extend radially outwardly and inclineproximally through the side wall to penetrate tissue of the left atrialappendage.
 2. A left atrial appendage occlusion device as in claim 1,wherein the compressible side wall has an uncompressed thickness of atleast about 0.5 mm.
 3. A left atrial appendage occlusion device as inclaim 1, wherein the compressible side wall has an uncompressedthickness of at least about 1.5 mm.
 4. A left atrial appendage occlusiondevice as in claim 1, wherein the compressible side wall extends in adistal direction beyond a distal end of the support by at least about 2mm in an unconstrained, expanded state.
 5. A left atrial appendageocclusion device as in claim 1, wherein the compressible side wallcomprises a foam having a plurality of interconnected reticulations andvoids, and further comprising a PTFE coating on at least some of theinterconnected reticulations.
 6. A left atrial appendage occlusiondevice as in claim 1, wherein the closed proximal end comprises a foamend wall.
 7. A left atrial appendage occlusion device as in claim 6,wherein the foam end wall further comprises a cover.
 8. A left atrialappendage occlusion device as in claim 7, wherein the cover comprisesePTFE.
 9. A left atrial appendage occlusion device as in claim 1,wherein the expandable support is self expandable.
 10. A left atrialappendage occlusion device as in claim 1, wherein the expandable supportis in the central cavity.
 11. A left atrial appendage occlusion deviceas in claim 1, wherein the tubular foam body is substantiallycylindrical in an unconstrained, expanded state.
 12. A self-expandable,atraumatic occlusion device configured to conform to the side wall of aleft atrial appendage, comprising: a compressible open cell foam body,having a tubular foam side wall and a central cavity; a self-expandablesupport within the cavity; anchors having tips configured to extendradially outwardly and incline proximally through the side wall topenetrate tissue of the left atrial appendage; and a proximal end wallforming a closed proximal end on the foam body; wherein the proximal endwall is positioned proximally of a proximal end of the support, and thefoam side wall extends distally beyond the distal end of the support toform a distal, atraumatic bumper for preventing contact between thesupport and a wall of the left atrial appendage in an implantation inwhich a central longitudinal axis of the occlusion device isnon-parallel to a primary longitudinal axis of the left atrialappendage.
 13. A left atrial appendage occlusion device, comprising: anexpandable tubular foam cup having a closed proximal end, a distal end,a tubular side wall and a proximal end wall, the side wall having athickness of at least about 1.0 mm and a porosity of at least about 85%open void content; an expandable frame configured to press the side wallinto conforming contact with a wall of the left atrial appendage; andanchors having tips configured to extend radially outwardly and inclineproximally through the side wall to penetrate tissue of the left atrialappendage.
 14. A left atrial appendage occlusion device as in claim 13,wherein the tubular side wall has a thickness of at least about 2 mm.15. A left atrial appendage occlusion device as in claim 14, wherein thetubular side wall has a void content of at least about 90%.
 16. A leftatrial appendage occlusion device as in claim 13, wherein the tubularside wall has an average pore size of at least about 100 microns.
 17. Aleft atrial appendage occlusion device as in claim 13, wherein thetubular side wall has an average pore size of at least about 200microns.
 18. A left atrial appendage occlusion device as in claim 13,wherein the tubular side wall is provided with a thromboresistantcoating.
 19. A left atrial appendage occlusion device as in claim 13,wherein the proximal end wall is provided with a thromboresistant cover.20. A left atrial appendage occlusion device as in claim 18, wherein thethromboresistant coating comprises PTFE.
 21. A left atrial appendageocclusion device as in claim 13, wherein the frame further comprises atleast three recapture struts inclining radially inwardly in the proximaldirection to a hub.
 22. A left atrial appendage occlusion device as inclaim 21, wherein the frame comprises a plurality of axially extendingside wall struts, with adjacent pairs of side wall struts joined at anapex.
 23. A left atrial appendage occlusion device as in claim 22,comprising at least six proximally facing apexes and at least sixdistally facing apexes.
 24. A left atrial appendage occlusion device asin claim 22, wherein each recapture strut is joined to a uniqueproximally facing apex on the frame.
 25. A left atrial appendageocclusion device as in claim 24, wherein the recapture struts areintegrally formed with the frame.
 26. A left atrial appendage occlusiondevice as in claim 21, further comprising a lumen through the hub.
 27. Aleft atrial appendage occlusion device as in claim 13, wherein theanchors are flexible anchors configured to extend through the foam sidewall at an inclined angle.
 28. A conformable left atrial appendage (LAA)occlusion device comprising: a compressible tubular foam wall with aclosed proximal end, the wall comprising a reticulated, cross linkedmatrix having at least about 90% void content, an average cell sizewithin the range of from about 250-500 microns, a wall thickness of atleast about 2 mm and a compressive strength of at least about 1 psi; andanchors having tips configured to extend radially outwardly and inclineproximally through the wall to penetrate tissue of the left atrialappendage.
 29. The conformable LAA occlusion device of claim 28, whereinthe compressive strength is within a range of from about 1 psi to about2 psi.
 30. The conformable LAA occlusion device of claim 28, furthercomprising an expandable support configured to compress the wall againsta wall of the LAA.